diff --git a/lib/spandex_datadog/api_server.ex b/lib/spandex_datadog/api_server.ex
index acbc288..5d00eb7 100644
--- a/lib/spandex_datadog/api_server.ex
+++ b/lib/spandex_datadog/api_server.ex
@@ -210,7 +210,7 @@ defmodule SpandexDatadog.ApiServer do
   def format(%Span{} = span), do: format(span, 1, [])
 
   @spec format(Span.t(), integer(), Keyword.t()) :: map()
-  def format(%Span{} = span, priority, _baggage) do
+  def format(%Span{} = span, priority, baggage) do
     %{
       trace_id: span.trace_id,
       span_id: span.id,
@@ -222,7 +222,7 @@ defmodule SpandexDatadog.ApiServer do
       resource: span.resource,
       service: span.service,
       type: span.type,
-      meta: meta(span),
+      meta: meta(span, baggage),
       metrics: %{
         _sampling_priority_v1: priority
       }
@@ -231,14 +231,15 @@ defmodule SpandexDatadog.ApiServer do
 
   # Private Helpers
 
-  @spec meta(Span.t()) :: map
-  defp meta(span) do
+  @spec meta(Span.t(), Keyword.t()) :: map
+  defp meta(span, baggage) do
     %{}
     |> add_datadog_meta(span)
     |> add_error_data(span)
     |> add_http_data(span)
     |> add_sql_data(span)
     |> add_tags(span)
+    |> add_baggage(baggage)
     |> Enum.reject(fn {_k, v} -> is_nil(v) end)
     |> Enum.into(%{})
   end
@@ -308,6 +309,11 @@ defmodule SpandexDatadog.ApiServer do
     Map.merge(meta, Enum.into(tags, %{}))
   end
 
+  @spec add_baggage(map, Keyword.t()) :: map
+  defp add_baggage(meta, baggage) do
+    Enum.into(baggage, meta)
+  end
+
   @spec error(nil | Keyword.t()) :: integer
   defp error(nil), do: 0
 
diff --git a/test/support/api_server_test.exs b/test/support/api_server_test.exs
index 5b8e349..bcb7977 100644
--- a/test/support/api_server_test.exs
+++ b/test/support/api_server_test.exs
@@ -162,4 +162,13 @@ defmodule SpandexDatadog.ApiServerTest do
       assert_received {:put_datadog_spans, ^formatted, ^url, _}
     end
   end
+
+  describe "ApiServer.format/3" do
+    test "it fills in Datadog metadata using the trace baggage", %{trace: trace} do
+      span = trace.spans |> Enum.at(0)
+      payload = ApiServer.format(span, 1, user_id: "U53R1D")
+
+      assert get_in(payload, [:meta, :user_id]) == "U53R1D"
+    end
+  end
 end