diff --git a/changelog.d/hb-age-references.fixed.md b/changelog.d/hb-age-references.fixed.md
new file mode 100644
index 0000000000..6e4e3e669c
--- /dev/null
+++ b/changelog.d/hb-age-references.fixed.md
@@ -0,0 +1 @@
+- Corrected Housing Benefit allowance age-threshold citations and added precise age-boundary regressions.
diff --git a/policyengine_uk/parameters/gov/dwp/housing_benefit/allowances/age_threshold/older.yaml b/policyengine_uk/parameters/gov/dwp/housing_benefit/allowances/age_threshold/older.yaml
index 9b1ea6b20f..4742454d73 100644
--- a/policyengine_uk/parameters/gov/dwp/housing_benefit/allowances/age_threshold/older.yaml
+++ b/policyengine_uk/parameters/gov/dwp/housing_benefit/allowances/age_threshold/older.yaml
@@ -4,8 +4,8 @@ metadata:
   period: year
   unit: year
   reference: 
-    - title: The Housing Benefit Regulations 2006 sec. 74
-      href: https://www.legislation.gov.uk/uksi/2006/213/made/data.pdf#page=73
+    - title: The Housing Benefit Regulations 2006, Schedule 3 paragraph 1
+      href: https://www.legislation.gov.uk/uksi/2006/213/schedule/3/paragraph/1
 
 values:
   2019-04-01: 25
diff --git a/policyengine_uk/parameters/gov/dwp/housing_benefit/allowances/age_threshold/younger.yaml b/policyengine_uk/parameters/gov/dwp/housing_benefit/allowances/age_threshold/younger.yaml
index 31c6ce9904..23923894f2 100644
--- a/policyengine_uk/parameters/gov/dwp/housing_benefit/allowances/age_threshold/younger.yaml
+++ b/policyengine_uk/parameters/gov/dwp/housing_benefit/allowances/age_threshold/younger.yaml
@@ -4,8 +4,8 @@ metadata:
   period: year
   unit: year
   reference: 
-    - title: The Housing Benefit Regulations 2006 sec. 74
-      href: https://www.legislation.gov.uk/uksi/2006/213/made/data.pdf#page=73
+    - title: The Housing Benefit Regulations 2006, Schedule 3 paragraph 1
+      href: https://www.legislation.gov.uk/uksi/2006/213/schedule/3/paragraph/1
 
 values:
   2019-04-01: 18
diff --git a/policyengine_uk/tests/policy/baseline/finance/benefit/family/housing_benefit/housing_benefit_applicable_amount.yaml b/policyengine_uk/tests/policy/baseline/finance/benefit/family/housing_benefit/housing_benefit_applicable_amount.yaml
index eeea8a6e58..263886d77d 100644
--- a/policyengine_uk/tests/policy/baseline/finance/benefit/family/housing_benefit/housing_benefit_applicable_amount.yaml
+++ b/policyengine_uk/tests/policy/baseline/finance/benefit/family/housing_benefit/housing_benefit_applicable_amount.yaml
@@ -115,3 +115,89 @@
         benefits_premiums: 0
   output:
     housing_benefit_applicable_amount: 108.3 * 52
+
+# Schedule 3 paragraph 1. Isolate the age bands from the separate premiums.
+
+- name: Single allowance immediately below 25
+  period: 2024
+  absolute_error_margin: 0.01
+  input:
+    housing_benefit_eligible: true
+    housing_benefit_pension_age_regulations_apply: false
+    benefits_premiums: 0
+    eldest_claimant_or_partner_age: 24
+    is_single_person: true
+    is_couple: false
+    is_lone_parent: false
+  output:
+    housing_benefit_applicable_amount: 71.7 * 52
+
+- name: Single allowance from age 25
+  period: 2024
+  absolute_error_margin: 0.01
+  input:
+    housing_benefit_eligible: true
+    housing_benefit_pension_age_regulations_apply: false
+    benefits_premiums: 0
+    eldest_claimant_or_partner_age: 25
+    is_single_person: true
+    is_couple: false
+    is_lone_parent: false
+  output:
+    housing_benefit_applicable_amount: 90.5 * 52
+
+- name: Couple allowance when both members are under 18
+  period: 2024
+  absolute_error_margin: 0.01
+  input:
+    housing_benefit_eligible: true
+    housing_benefit_pension_age_regulations_apply: false
+    benefits_premiums: 0
+    eldest_claimant_or_partner_age: 17
+    is_single_person: false
+    is_couple: true
+    is_lone_parent: false
+  output:
+    housing_benefit_applicable_amount: 108.3 * 52
+
+- name: Couple allowance when a member turns 18
+  period: 2024
+  absolute_error_margin: 0.01
+  input:
+    housing_benefit_eligible: true
+    housing_benefit_pension_age_regulations_apply: false
+    benefits_premiums: 0
+    eldest_claimant_or_partner_age: 18
+    is_single_person: false
+    is_couple: true
+    is_lone_parent: false
+  output:
+    housing_benefit_applicable_amount: 142.25 * 52
+
+- name: Lone-parent allowance immediately below 18
+  period: 2024
+  absolute_error_margin: 0.01
+  input:
+    housing_benefit_eligible: true
+    housing_benefit_pension_age_regulations_apply: false
+    benefits_premiums: 0
+    eldest_claimant_or_partner_age: 17
+    is_single_person: false
+    is_couple: false
+    is_lone_parent: true
+  output:
+    housing_benefit_applicable_amount: 71.7 * 52
+
+- name: Lone-parent allowance from age 18
+  period: 2024
+  absolute_error_margin: 0.01
+  input:
+    housing_benefit_eligible: true
+    housing_benefit_pension_age_regulations_apply: false
+    benefits_premiums: 0
+    eldest_claimant_or_partner_age: 18
+    is_single_person: false
+    is_couple: false
+    is_lone_parent: true
+  output:
+    housing_benefit_applicable_amount: 90.5 * 52