diff --git a/changelog_entry.yaml b/changelog_entry.yaml
index e69de29bb..340e6e425 100644
--- a/changelog_entry.yaml
+++ b/changelog_entry.yaml
@@ -0,0 +1,4 @@
+- bump: patch
+  changes:
+    fixed:
+    - Add is_married to FRS benefit unit dataset
\ No newline at end of file
diff --git a/policyengine_uk_data/datasets/frs.py b/policyengine_uk_data/datasets/frs.py
index 9153ef1c0..564bf0303 100644
--- a/policyengine_uk_data/datasets/frs.py
+++ b/policyengine_uk_data/datasets/frs.py
@@ -797,6 +797,10 @@ def determine_education_level(fted_val, typeed2_val, age_val):
         extended_hours_values
     )
 
+    # Add marital status at the benefit unit level
+
+    pe_benunit["is_married"] = frs["benunit"].famtypb2.isin([5, 7])
+
     dataset = UKSingleYearDataset(
         person=pe_person,
         benunit=pe_benunit,
diff --git a/policyengine_uk_data/tests/microsimulation/reforms_config.yaml b/policyengine_uk_data/tests/microsimulation/reforms_config.yaml
index a8f5c9b44..8472544e1 100644
--- a/policyengine_uk_data/tests/microsimulation/reforms_config.yaml
+++ b/policyengine_uk_data/tests/microsimulation/reforms_config.yaml
@@ -16,7 +16,7 @@ reforms:
   parameters:
     gov.hmrc.child_benefit.amount.additional: 25
 - name: Reduce Universal Credit taper rate to 20%
-  expected_impact: -33.7
+  expected_impact: -36.7
   parameters:
     gov.dwp.universal_credit.means_test.reduction_rate: 0.2
 - name: Raise Class 1 main employee NICs rate to 10%