diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2a92ee79e..9d2a59461 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [0.2.6] - 2023-11-14 17:00:00
+
+### Added
+
+- Updates Montana tax logic.
+
 ## [0.2.5] - 2023-10-24 22:00:00
 
 ### Added
@@ -185,7 +191,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - First prototype version based off of openfisca-us and tax-calculator.
 
 
-
+[0.2.6]: https://github.com/TheCGO/fiscalsim-us/compare/v0.2.5...v0.2.6
 [0.2.5]: https://github.com/TheCGO/fiscalsim-us/compare/v0.2.4...v0.2.5
 [0.2.4]: https://github.com/TheCGO/fiscalsim-us/compare/v0.2.3...v0.2.4
 [0.2.3]: https://github.com/TheCGO/fiscalsim-us/compare/v0.2.2...v0.2.3
diff --git a/changelog.yaml b/changelog.yaml
index aa9a8c1fa..baf663707 100644
--- a/changelog.yaml
+++ b/changelog.yaml
@@ -169,3 +169,8 @@
       - Updated environment.yml and build_and_test.yml to allow for python 3.11
       - Updated Virginia tax logic with correct mapping from federal filing status to state filing status.
   date: 2023-10-24 22:00:00
+- bump: patch
+  changes:
+    added:
+      - Updates Montana tax logic
+  date: 2023-11-14 17:00:00
diff --git a/fiscalsim_us/parameters/gov/states/mt/tax/income/deductions/itemized/itemized_deductions.yaml b/fiscalsim_us/parameters/gov/states/mt/tax/income/deductions/itemized/itemized_deductions.yaml
new file mode 100644
index 000000000..eb9625433
--- /dev/null
+++ b/fiscalsim_us/parameters/gov/states/mt/tax/income/deductions/itemized/itemized_deductions.yaml
@@ -0,0 +1,24 @@
+description: Montana deductions from taxable income if itemizing (that are not available if not itemizing).
+values:
+  2022-01-01:
+    - mt_medical_and_dental_expenses_deduction
+    - mt_medical_premiums_deduction
+    - mt_long_term_care_premiums_deduction
+    - mt_federal_income_tax_deduction
+    - mt_state_local_tax_deduction
+    - mt_light_vehicle_registration_deduction
+    - mt_per_capita_livestock_deduction
+    - mt_other_taxes_paid_deduction
+    - mt_home_mortage_interest_deduction
+    - mt_investment_interest_deduction
+    - mt_charitable_cash_deduction
+    - mt_charitable_noncash_deduction
+    - mt_charitable_carryover_deduction
+    - mt_child_care_expense_deduction
+    - mt_casualty_loss_deduction
+    - mt_political_contributions_deduction
+    - mt_gambling_loss_deduction
+    - mt_other_deduction
+metadata:
+  unit: variable
+  label: montana itemized deductions
diff --git a/fiscalsim_us/parameters/gov/states/mt/tax/income/deductions/itemized/medical_dental/rate.yaml b/fiscalsim_us/parameters/gov/states/mt/tax/income/deductions/itemized/medical_dental/rate.yaml
new file mode 100644
index 000000000..c1fb09bf7
--- /dev/null
+++ b/fiscalsim_us/parameters/gov/states/mt/tax/income/deductions/itemized/medical_dental/rate.yaml
@@ -0,0 +1,9 @@
+description: Montana percentage of adjusted gross income that your medical and dental expenses are subject to.
+values:
+  2022-01-01: 0.075
+metadata:
+  unit: year
+  label: Montana itemized medical and dental rate
+  reference:
+    title: Montana Individual Tax Return Form 2 | Itemized Deductions Scedule | Line 1c
+    href: https://mtrevenue.gov/wp-content/uploads/dlm_uploads/2023/05/Montana-Idividiual-Income-Tax-Return-Form-2-2022v6.2.pdf
diff --git a/fiscalsim_us/parameters/gov/states/mt/tax/income/deductions/itemized/misc/political_contributions_cap.yaml b/fiscalsim_us/parameters/gov/states/mt/tax/income/deductions/itemized/misc/political_contributions_cap.yaml
new file mode 100644
index 000000000..bbaa6eb2f
--- /dev/null
+++ b/fiscalsim_us/parameters/gov/states/mt/tax/income/deductions/itemized/misc/political_contributions_cap.yaml
@@ -0,0 +1,9 @@
+description: Montana cap that the political contributions and limited by per taxpayer
+values:
+  2022-01-01: 100
+metadata:
+  unit: year
+  label: Montana political contributions cap
+  reference:
+    title: Montana Individual Tax Return Form 2 | Itemized Deductions Scedule | Line 16
+    href: https://mtrevenue.gov/wp-content/uploads/dlm_uploads/2023/05/Montana-Idividiual-Income-Tax-Return-Form-2-2022v6.2.pdf
diff --git a/fiscalsim_us/parameters/gov/states/mt/tax/income/deductions/itemized/misc/salt_cap.yaml b/fiscalsim_us/parameters/gov/states/mt/tax/income/deductions/itemized/misc/salt_cap.yaml
new file mode 100644
index 000000000..f27723800
--- /dev/null
+++ b/fiscalsim_us/parameters/gov/states/mt/tax/income/deductions/itemized/misc/salt_cap.yaml
@@ -0,0 +1,21 @@
+description: Maximum amount of state and local income, sales and real estate tax deductions allowed in montana.
+metadata:
+  unit: currency-USD
+  period: year
+  name: mt_salt_cap
+  label: Montana SALT cap
+HEAD_OF_HOUSEHOLD:
+  values:
+    2022-01-01: 10_000
+JOINT:
+  values:
+    2022-01-01: 10_000
+SEPARATE:
+  values:
+    2022-01-01: 5_000
+SINGLE:
+  values:
+    2022-01-01: 10000
+WIDOW:
+  values:
+    2022-01-01: 10000
diff --git a/fiscalsim_us/parameters/gov/states/mt/tax/income/deductions/standard/max.yaml b/fiscalsim_us/parameters/gov/states/mt/tax/income/deductions/standard/max.yaml
index 1025c46b4..abff2c2d5 100644
--- a/fiscalsim_us/parameters/gov/states/mt/tax/income/deductions/standard/max.yaml
+++ b/fiscalsim_us/parameters/gov/states/mt/tax/income/deductions/standard/max.yaml
@@ -1,4 +1,5 @@
 description: Montana provides this maximum standard deduction amount, based on filing status.
+
 metadata:
   label: Montana standard deduction max amount
   period: year
@@ -8,7 +9,7 @@ metadata:
   reference:
     - title: MT Code, Income Tax - Deductions, § 42-15-523 (2)
       href: https://rules.mt.gov/gateway/RuleNo.asp?RN=42%2E15%2E523
-    - title: Montana Tax Form 2022 | Standard Deduction | Line 3
+    - title: This refers to line 3 of the standard deduction worksheet on Montana tax form 2. | Montana Tax Form 2022 | Standard Deduction | Line 3
       href: https://mtrevenue.gov/wp-content/uploads/dlm_uploads/2023/05/Montana-Idividiual-Income-Tax-Return-Form-2-2022v6.2.pdf#page=7
     - title: Montana Tax Form 2021 | Standard Deduction | Line 3
       href: https://mtrevenue.gov/wp-content/uploads/mdocs/form%202%202021.pdf#page=7
diff --git a/fiscalsim_us/parameters/gov/states/mt/tax/income/deductions/standard/min.yaml b/fiscalsim_us/parameters/gov/states/mt/tax/income/deductions/standard/min.yaml
index 619a2f39c..97aca3e3f 100644
--- a/fiscalsim_us/parameters/gov/states/mt/tax/income/deductions/standard/min.yaml
+++ b/fiscalsim_us/parameters/gov/states/mt/tax/income/deductions/standard/min.yaml
@@ -1,4 +1,5 @@
 description: Montana provides a minimum standard deduction of this amount, based on filing status.
+
 metadata:
   label: Montana minimum standard deduction
   period: year
@@ -6,9 +7,13 @@ metadata:
   breakdown:
     - filing_status
   reference:
+    - title: Increase each year with inflation (repealed effective January 1, 2024)
+      href: https://leg.mt.gov/bills/mca/title_0150/chapter_0300/part_0210/section_0320/0150-0300-0210-0320.html
+    - title: Title 15 Chapter 30 Individual Income Tax Part 21. Rate and General Provisions, Standard Deduction Rule 15-30-2132
+      href: https://leg.mt.gov/bills/mca/title_0150/chapter_0300/part_0210/section_0320/0150-0300-0210-0320.html
     - title: MT Code, Income Tax - Deductions, § 42-15-523 (2)
       href: https://rules.mt.gov/gateway/RuleNo.asp?RN=42%2E15%2E523
-    - title: Montana Tax Form 2022 | Standard Deduction | Line 5
+    - title: This refers to line 5 of the standard deduction worksheet on Montana tax form 2 | Montana Tax Form 2022 | Standard Deduction | Line 5
       href: https://mtrevenue.gov/wp-content/uploads/dlm_uploads/2023/05/Montana-Idividiual-Income-Tax-Return-Form-2-2022v6.2.pdf#page=7
     - title: Montana Tax Form 2021 | Standard Deduction | Line 5
       href: https://mtrevenue.gov/wp-content/uploads/mdocs/form%202%202021.pdf#page=7
diff --git a/fiscalsim_us/parameters/gov/states/mt/tax/income/exemptions/amount.yaml b/fiscalsim_us/parameters/gov/states/mt/tax/income/exemptions/amount.yaml
index 282cb22bc..1186d658b 100644
--- a/fiscalsim_us/parameters/gov/states/mt/tax/income/exemptions/amount.yaml
+++ b/fiscalsim_us/parameters/gov/states/mt/tax/income/exemptions/amount.yaml
@@ -4,6 +4,8 @@ values:
   2022-01-01: 2_710
 metadata:
   reference:
+    - title: Defined in the law as $1900 beginning after December 31, 2004, indexed by inflation. (Repealed effective January 1, 2024)
+      href: https://leg.mt.gov/bills/mca/title_0150/chapter_0300/part_0210/section_0140/0150-0300-0210-0140.html
     - title: "Montana Tax Form 2021 | Exemptions | Line 16"
       href: https://mtrevenue.gov/wp-content/uploads/mdocs/form%202%202021.pdf#page=1
     - title: "Montana Tax Form 2022 | Exemptions | Line 16"
diff --git a/fiscalsim_us/parameters/gov/states/mt/tax/income/main/head_of_household.yaml b/fiscalsim_us/parameters/gov/states/mt/tax/income/rates/head_of_household.yaml
similarity index 100%
rename from fiscalsim_us/parameters/gov/states/mt/tax/income/main/head_of_household.yaml
rename to fiscalsim_us/parameters/gov/states/mt/tax/income/rates/head_of_household.yaml
diff --git a/fiscalsim_us/parameters/gov/states/mt/tax/income/main/joint.yaml b/fiscalsim_us/parameters/gov/states/mt/tax/income/rates/joint.yaml
similarity index 100%
rename from fiscalsim_us/parameters/gov/states/mt/tax/income/main/joint.yaml
rename to fiscalsim_us/parameters/gov/states/mt/tax/income/rates/joint.yaml
diff --git a/fiscalsim_us/parameters/gov/states/mt/tax/income/main/separate.yaml b/fiscalsim_us/parameters/gov/states/mt/tax/income/rates/separate.yaml
similarity index 100%
rename from fiscalsim_us/parameters/gov/states/mt/tax/income/main/separate.yaml
rename to fiscalsim_us/parameters/gov/states/mt/tax/income/rates/separate.yaml
diff --git a/fiscalsim_us/parameters/gov/states/mt/tax/income/main/single.yaml b/fiscalsim_us/parameters/gov/states/mt/tax/income/rates/single.yaml
similarity index 100%
rename from fiscalsim_us/parameters/gov/states/mt/tax/income/main/single.yaml
rename to fiscalsim_us/parameters/gov/states/mt/tax/income/rates/single.yaml
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/additions_subtractions/mt_income_additions.py b/fiscalsim_us/variables/gov/states/mt/tax/income/additions_subtractions/mt_income_additions.py
new file mode 100644
index 000000000..46cd65290
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/additions_subtractions/mt_income_additions.py
@@ -0,0 +1,16 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_additions_to_income(Variable):
+    """
+    Line 12 on Montana 2022 Individual Income Tax return form 2. These
+    additions to income include the categories that are listed
+    in Montana Additions Schedule on page 4 of Montana 2022 Individual Income Tax return form 2
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "MT additions to income"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/additions_subtractions/mt_income_subtractions.py b/fiscalsim_us/variables/gov/states/mt/tax/income/additions_subtractions/mt_income_subtractions.py
new file mode 100644
index 000000000..ad16d3fe8
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/additions_subtractions/mt_income_subtractions.py
@@ -0,0 +1,16 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_subtractions_to_income(Variable):
+    """
+    Line 13 on Montana 2022 Individual Income Tax return form 2. These
+    subtractions to income include the categories that are listed
+    in Montana Subtractions Schedule on page 5 of Montana 2022 Individual Income Tax return form 2
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "MT subtractions to income"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/mt_eitc.py b/fiscalsim_us/variables/gov/states/mt/tax/income/credits/mt_eitc.py
similarity index 100%
rename from fiscalsim_us/variables/gov/states/mt/tax/income/mt_eitc.py
rename to fiscalsim_us/variables/gov/states/mt/tax/income/credits/mt_eitc.py
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/credits/mt_nonrefundable_credits.py b/fiscalsim_us/variables/gov/states/mt/tax/income/credits/mt_nonrefundable_credits.py
new file mode 100644
index 000000000..801072b0f
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/credits/mt_nonrefundable_credits.py
@@ -0,0 +1,16 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_nonrefundable_credits(Variable):
+    """
+    Line 19 of Montana state individual tax return form 2
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "Montana refundable credits"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
+
+    adds = "gov.states.mt.tax.income.credits.non_refundable"
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/mt_refundable_credits.py b/fiscalsim_us/variables/gov/states/mt/tax/income/credits/mt_refundable_credits.py
similarity index 77%
rename from fiscalsim_us/variables/gov/states/mt/tax/income/mt_refundable_credits.py
rename to fiscalsim_us/variables/gov/states/mt/tax/income/credits/mt_refundable_credits.py
index a0f13f36d..7f6edae61 100644
--- a/fiscalsim_us/variables/gov/states/mt/tax/income/mt_refundable_credits.py
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/credits/mt_refundable_credits.py
@@ -2,6 +2,10 @@
 
 
 class mt_refundable_credits(Variable):
+    """
+    Line 22 on Montana individual tax return form 2
+    """
+
     value_type = float
     entity = TaxUnit
     label = "Montana refundable credits"
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/credits/mt_tax_after_nonrefundable_credits.py b/fiscalsim_us/variables/gov/states/mt/tax/income/credits/mt_tax_after_nonrefundable_credits.py
new file mode 100644
index 000000000..b79db07a1
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/credits/mt_tax_after_nonrefundable_credits.py
@@ -0,0 +1,21 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_tax_after_nonrefundable_credits(Variable):
+    """
+    Line 20 on Montana individual tax return form 2
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "Montana refundable credits"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
+
+    def formula(tax_unit, period, parameter):
+        nonrefundable = tax_unit("mt_nonrefundable_credits")
+        incometaxbeforecredits = tax_unit(
+            "mt_income_tax_before_refundable_credits"
+        )
+        return incometaxbeforecredits - nonrefundable
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_casualty_deduction.py b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_casualty_deduction.py
new file mode 100644
index 000000000..43528bfb9
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_casualty_deduction.py
@@ -0,0 +1,19 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_casualty_loss_deduction(Variable):
+    """
+    Line 15 on Montana itemized deductions schedule
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "Montana casualty and theft losses"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
+
+    def formula(tax_unit, period, parameters):
+        deduction = (tax_unit, period, ["casualty_loss_deduction"])
+
+        return deduction
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_charitable_carryover_deduction.py b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_charitable_carryover_deduction.py
new file mode 100644
index 000000000..0deba83f6
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_charitable_carryover_deduction.py
@@ -0,0 +1,16 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_charitable_carryover_deduction(Variable):
+    """
+    Line 13 on Montana itemized deductions schedule
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = (
+        "Montana charitable carryover donation from previous year deduction"
+    )
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_charitable_cash_deduction.py b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_charitable_cash_deduction.py
new file mode 100644
index 000000000..6416b5470
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_charitable_cash_deduction.py
@@ -0,0 +1,22 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_charitable_cash_deduction(Variable):
+    """
+    Line 11 on Montana itemized deductions schedule
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "Montana charitable cash donation deduction"
+    unit = USD
+    documentation = (
+        "Montana deduction from taxable income for charitable cash donations."
+    )
+    definition_period = YEAR
+    defined_for = StateCode.MT
+
+    def formula(tax_unit, period, parameters):
+        cash_donations = add(tax_unit, period, ["charitable_cash_donations"])
+
+        return cash_donations
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_charitable_noncash_deduction.py b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_charitable_noncash_deduction.py
new file mode 100644
index 000000000..f6e3e89b9
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_charitable_noncash_deduction.py
@@ -0,0 +1,19 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_charitable_noncash_deduction(Variable):
+    """
+    Line 12 on Montana itemized deductions schedule
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "Montana charitable non-cash donation deduction"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
+
+    def formula(tax_unit, period, parameters):
+        noncash_donations = tax_unit(period, ["charitable_non_cash_donations"])
+
+        return noncash_donations
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_child_care_expenses_deduction.py b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_child_care_expenses_deduction.py
new file mode 100644
index 000000000..109a535ff
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_child_care_expenses_deduction.py
@@ -0,0 +1,14 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_child_care_expense_deduction(Variable):
+    """
+    Line 14 on Montana itemized deductions schedule
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "Montana child and dependent care expenses"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_federal_income_tax_deduction.py b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_federal_income_tax_deduction.py
new file mode 100644
index 000000000..645ea5643
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_federal_income_tax_deduction.py
@@ -0,0 +1,22 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_federal_income_tax_deduction(Variable):
+    """
+    Line 4 on itemized deductions schedule
+    Includes the following
+    *Federal income tax withheld
+    *Federal estimated tax payments
+    *Prior year federal income taxes
+    *Other back year federal income taxes
+    Add each of those together but not more then $5,000 if you are single,
+        head of household, or married filing sperarately; or $10,000 if you
+        are married filing jointly
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "Montana federal tax paid/withheld in prior year"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_gambling_loss_deduction.py b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_gambling_loss_deduction.py
new file mode 100644
index 000000000..d1ccc1324
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_gambling_loss_deduction.py
@@ -0,0 +1,15 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_gambling_loss_deduction(Variable):
+    """
+    Line 17 on itemized deductions schedule
+    Limited to what it allowed under federal law
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "Montana gambling loss deduction"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_home_mortage_interest_deduction.py b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_home_mortage_interest_deduction.py
new file mode 100644
index 000000000..41da10f56
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_home_mortage_interest_deduction.py
@@ -0,0 +1,15 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_home_mortage_interest_deduction(Variable):
+    """
+    Line 9 on itemized deductions schedule
+    Home mortgage interst and points
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "Montana home mortage interest deduction"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_investment_interest_deduction.py b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_investment_interest_deduction.py
new file mode 100644
index 000000000..cc603cf7d
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_investment_interest_deduction.py
@@ -0,0 +1,19 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_investment_interest_deduction(Variable):
+    """
+    Line 10 on itemized deductions schedule
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "Montana investment interest deduction"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
+
+    def formula(tax_unit, period, parameters):
+        contributions = tax_unit("investment_income_form_4952")
+
+        return contributions
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_itemized_deductions.py b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_itemized_deductions.py
new file mode 100644
index 000000000..4edc58fa2
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_itemized_deductions.py
@@ -0,0 +1,22 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_itemized_deduction(Variable):
+    """
+    See itemized deduction schedule on page 7 of the Montana individual tax return form 2 for how to calculate
+    Line 15 on Montana individual tax return form 2
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "MT itemized deduction"
+    unit = USD
+    definition_period = YEAR
+    documentation = "Montana itemized deduction"
+    reference = (
+        "https://mtrevenue.gov/wp-content/uploads/dlm_uploads/2023/05/Montana-Idividiual-Income-Tax-Return-Form-2-2022v6.2.pdf"
+        "https://mtrevenue.gov/wp-content/uploads/dlm_uploads/2022/12/Form-2-2022-Instructions.pdf"
+    )
+    defined_for = StateCode.MT
+
+    adds = "gov.states.mt.tax.income.deductions.itemized.itemized_deductions"
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_light_vehicle_registration_deduction.py b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_light_vehicle_registration_deduction.py
new file mode 100644
index 000000000..48d2c9cee
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_light_vehicle_registration_deduction.py
@@ -0,0 +1,14 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_light_vehicle_registration_deduction(Variable):
+    """
+    Line 6 on itemized deductions schedule
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "Montana light vehicle registration fees"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_long_term_care_premiums.py b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_long_term_care_premiums.py
new file mode 100644
index 000000000..76d704bee
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_long_term_care_premiums.py
@@ -0,0 +1,15 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_long_term_care_premiums_deduction(Variable):
+    """
+    Line 3 on itemized deductions schedule
+    Long-term core insurance premiums not deducted elsewhere on your return
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "Montana long-term care insurance premiums deduction"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_medical_dental_expense.py b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_medical_dental_expense.py
new file mode 100644
index 000000000..a9d664784
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_medical_dental_expense.py
@@ -0,0 +1,14 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_medical_dental_expense(Variable):
+    """
+    Line 1a on itemized deductions schedule
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "Montana medical and dental expense"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_medical_dental_expenses_deduction.py b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_medical_dental_expenses_deduction.py
new file mode 100644
index 000000000..01bce8d9b
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_medical_dental_expenses_deduction.py
@@ -0,0 +1,24 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_medical_dental_expenses_deduction(Variable):
+    """
+    Line 1 on itemized deductions schedule
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "Montana medical and dental expense deduction"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
+
+    def formula(tax_unit, period, parameters):
+        p = parameters(
+            period
+        ).gov.states.mt.tax.income.deductions.itemized.medical_dental
+        line1a = tax_unit("mt_medical_dental_expense", period)
+        line1b = tax_unit("mt_agi", period)
+        line1c = line1b * p.rate
+
+        return max_(line1c - line1a, 0)
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_medical_premiums_deduction.py b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_medical_premiums_deduction.py
new file mode 100644
index 000000000..2befc6cce
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_medical_premiums_deduction.py
@@ -0,0 +1,15 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_medical_premiums_deduction(Variable):
+    """
+    Line 2 on itemized deductions schedule
+    Medical insurance premiums not deducted elsewhere on the return
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "Montana medical insurance premiums"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/mt_taxable_income.py b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_other_deduction.py
similarity index 53%
rename from fiscalsim_us/variables/gov/states/mt/tax/income/mt_taxable_income.py
rename to fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_other_deduction.py
index 11d03ff6e..9a3699b9c 100644
--- a/fiscalsim_us/variables/gov/states/mt/tax/income/mt_taxable_income.py
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_other_deduction.py
@@ -1,10 +1,14 @@
 from fiscalsim_us.model_api import *
 
 
-class mt_taxable_income(Variable):
+class mt_other_deduction(Variable):
+    """
+    Line 18 on itemized deductions schedule
+    """
+
     value_type = float
     entity = TaxUnit
-    label = "Montana taxable income"
+    label = "Montana other deductions"
     unit = USD
     definition_period = YEAR
     defined_for = StateCode.MT
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_other_taxes_paid_deduction.py b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_other_taxes_paid_deduction.py
new file mode 100644
index 000000000..f7a342306
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_other_taxes_paid_deduction.py
@@ -0,0 +1,14 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_other_taxes_paid_deduction(Variable):
+    """
+    Line 8 on itemized deductions schedule
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "Montana other deductible taxes paid"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_per_capita_livestock_deduction.py b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_per_capita_livestock_deduction.py
new file mode 100644
index 000000000..746687329
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_per_capita_livestock_deduction.py
@@ -0,0 +1,14 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_per_capita_livestock_deduction(Variable):
+    """
+    Line 7 on itemized deductions schedule
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "Montana per capita livestock fees"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/mt_agi.py b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_political_contributions.py
similarity index 63%
rename from fiscalsim_us/variables/gov/states/mt/tax/income/mt_agi.py
rename to fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_political_contributions.py
index 5b6ed8601..13ee64bda 100644
--- a/fiscalsim_us/variables/gov/states/mt/tax/income/mt_agi.py
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_political_contributions.py
@@ -1,10 +1,10 @@
 from fiscalsim_us.model_api import *
 
 
-class mt_agi(Variable):
+class mt_political_contributions(Variable):
     value_type = float
     entity = TaxUnit
-    label = "Montana Adjusted Gross Income"
+    label = "Montana political contributions"
     unit = USD
     definition_period = YEAR
     defined_for = StateCode.MT
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_political_contributions_deduction.py b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_political_contributions_deduction.py
new file mode 100644
index 000000000..74fbc3d28
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_political_contributions_deduction.py
@@ -0,0 +1,24 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_political_contributions_deduction(Variable):
+    """
+    Line 16 on itemized deductions schedule
+    Limited to $100 per taxpayer
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "Montana political contributions deduction"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
+
+    def formula(tax_unit, period, parameters):
+        p = parameters(
+            period
+        ).gov.states.mt.tax.income.deductions.itemized.misc
+        cap = p.political_contribution_cap
+        contributions = tax_unit("mt_political_contributions")
+
+        return min_(cap, contributions)
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_state_local_tax_deduction.py b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_state_local_tax_deduction.py
new file mode 100644
index 000000000..7fe46addc
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/deductions/itemized/mt_state_local_tax_deduction.py
@@ -0,0 +1,37 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_state_local_tax_deduction(Variable):
+    """
+    Line 5 on itemized deductions schedule
+    Includes the following
+    *General state and local sales taxes
+    *Local income taxes
+    *Real estate taxes paid
+    *Value-based personal property taxes
+    Add each of those together but not more than $10,000 if you are single,
+        head of household, or married filing jointly; or $5,000 if you
+        are married filing separately
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "Montana state and local taxes in prior year"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
+
+    def formula(tax_unit, period, parameters):
+        salt_amount = add(
+            tax_unit,
+            period,
+            [
+                "statelocal_sales_or_prior_inctax",
+                "real_estate_taxes",
+            ],
+        )
+        salt = parameters(
+            period
+        ).gov.state.mt.tax.income.deductions.itemized.misc
+        cap = salt.salt_cap[tax_unit("filing_status", period)]
+        return min(cap, salt_amount)
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/main/mt_agi.py b/fiscalsim_us/variables/gov/states/mt/tax/income/main/mt_agi.py
new file mode 100644
index 000000000..6475c34b6
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/main/mt_agi.py
@@ -0,0 +1,18 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_agi(Variable):
+    """
+    Montana adjusted gross income. Line 14 on Montana individual income tax
+    return form 2
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "MT adjusted gross income"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
+
+    adds = ["adjusted_gross_income", "mt_income_additions"]
+    subtracts = ["mt_income_subtractions"]
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/main/mt_contributions_penalties_interest.py b/fiscalsim_us/variables/gov/states/mt/tax/income/main/mt_contributions_penalties_interest.py
new file mode 100644
index 000000000..96877a7ce
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/main/mt_contributions_penalties_interest.py
@@ -0,0 +1,14 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_contributions_penalties_interest(Variable):
+    """
+    Line 24 on Montana individual income tax retrun form 2
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "Montana contributions penatlites and interest"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/mt_income_tax.py b/fiscalsim_us/variables/gov/states/mt/tax/income/main/mt_income_tax.py
similarity index 100%
rename from fiscalsim_us/variables/gov/states/mt/tax/income/mt_income_tax.py
rename to fiscalsim_us/variables/gov/states/mt/tax/income/main/mt_income_tax.py
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/mt_income_tax_before_refundable_credits.py b/fiscalsim_us/variables/gov/states/mt/tax/income/main/mt_income_tax_before_refundable_credits.py
similarity index 87%
rename from fiscalsim_us/variables/gov/states/mt/tax/income/mt_income_tax_before_refundable_credits.py
rename to fiscalsim_us/variables/gov/states/mt/tax/income/main/mt_income_tax_before_refundable_credits.py
index 5f2bbf932..dfdcca9a3 100644
--- a/fiscalsim_us/variables/gov/states/mt/tax/income/mt_income_tax_before_refundable_credits.py
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/main/mt_income_tax_before_refundable_credits.py
@@ -2,6 +2,10 @@
 
 
 class mt_income_tax_before_refundable_credits(Variable):
+    """
+    Line 18 of Montana state individual tax return form 2
+    """
+
     value_type = float
     entity = TaxUnit
     label = "Montana income tax before refundable credits"
@@ -11,7 +15,7 @@ class mt_income_tax_before_refundable_credits(Variable):
 
     def formula(tax_unit, period, parameters):
         income = tax_unit("mt_taxable_income", period)
-        p = parameters(period).gov.states.mt.tax.income.main
+        p = parameters(period).gov.states.mt.tax.income.rates
         filing_status = tax_unit("filing_status", period)
         status = filing_status.possible_values
         return select(
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/main/mt_tax_due.py b/fiscalsim_us/variables/gov/states/mt/tax/income/main/mt_tax_due.py
new file mode 100644
index 000000000..7a63d0727
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/main/mt_tax_due.py
@@ -0,0 +1,21 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_tax_due(Variable):
+    """
+    Line 26 on Montana state individual tax return form 2
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "Montana tax due"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
+
+
+def formula(tax_unit, period, parameters):
+    line20 = tax_unit("mt_tax_after_nonrefundable_credits")
+    line25 = tax_unit("mt_total_payments")
+
+    return where(line25 < line20, line20 - line25, 0)
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/main/mt_tax_overpaid.py b/fiscalsim_us/variables/gov/states/mt/tax/income/main/mt_tax_overpaid.py
new file mode 100644
index 000000000..0af757b01
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/main/mt_tax_overpaid.py
@@ -0,0 +1,21 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_tax_overpaid(Variable):
+    """
+    Line 27 on Montana state individual tax return form 2
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "Montana tax overpaid"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
+
+
+def formula(tax_unit, period, parameters):
+    line20 = tax_unit("mt_tax_after_nonrefundable_credits")
+    line25 = tax_unit("mt_total_payments")
+
+    return where(line25 > line20, line25 - line20, 0)
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/main/mt_taxable_income.py b/fiscalsim_us/variables/gov/states/mt/tax/income/main/mt_taxable_income.py
new file mode 100644
index 000000000..5ff513a2a
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/main/mt_taxable_income.py
@@ -0,0 +1,25 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_taxable_income(Variable):
+    """
+    Line 17 on Montana state individual tax return form 2
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "Montana taxable income"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
+
+
+def formula(tax_unit, period, parameters):
+    std_ded = tax_unit("mt_standard_deduction", period)
+    itm_ded = tax_unit("mt_itemized_deductions", period)
+    deductions = where(itm_ded > std_ded, itm_ded, std_ded)
+    exemptions = tax_unit("mt_exemptions", period)
+    return max(
+        0,
+        tax_unit("mt_agi", period) - deductions - exemptions,
+    )
diff --git a/fiscalsim_us/variables/gov/states/mt/tax/income/main/mt_total_payments.py b/fiscalsim_us/variables/gov/states/mt/tax/income/main/mt_total_payments.py
new file mode 100644
index 000000000..c35280c58
--- /dev/null
+++ b/fiscalsim_us/variables/gov/states/mt/tax/income/main/mt_total_payments.py
@@ -0,0 +1,17 @@
+from fiscalsim_us.model_api import *
+
+
+class mt_total_payments(Variable):
+    """
+    Line 25 on Montana individual income tax retrun form 2
+    """
+
+    value_type = float
+    entity = TaxUnit
+    label = "Montana total payments"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.MT
+
+    adds = ["mt_refundable_credits", "mt_eitc"]
+    subtracts = ["mt_contributions_penalties_interest"]
diff --git a/fiscalsim_us/variables/gov/states/va/tax/income/va_tax_credit_for_low_income_individuals.py b/fiscalsim_us/variables/gov/states/va/tax/income/va_tax_credit_for_low_income_individuals.py
index 6001872c2..49deff764 100644
--- a/fiscalsim_us/variables/gov/states/va/tax/income/va_tax_credit_for_low_income_individuals.py
+++ b/fiscalsim_us/variables/gov/states/va/tax/income/va_tax_credit_for_low_income_individuals.py
@@ -38,6 +38,6 @@ def formula(tax_unit, period, parameters):
         line_14 = fed_eitc
         line_15 = line_14 * eitc_rate
         line_16 = where(line_15 > line_13, line_15, line_13)
-        line_17 = where(net_tax > line_16, line_16, 0)
+        line_17 = where(net_tax > line_16, line_16, net_tax)
 
-        return line_17
+        return where(total_agi < threshold, line_17, 0)
diff --git a/setup.py b/setup.py
index 0e2f3e663..622ee9994 100644
--- a/setup.py
+++ b/setup.py
@@ -7,7 +7,7 @@
 
 setup(
     name="fiscalsim-us",
-    version="0.2.5",
+    version="0.2.6",
     author="Center for Growth and Opportunity at Utah State University (CGO)",
     author_email="fiscalsim@thecgo.org",
     long_description=readme,