diff --git a/roles/custom/matrix-synapse/molecule/default/verify.yml b/roles/custom/matrix-synapse/molecule/default/verify.yml
index 450e1345d..b8232ef60 100644
--- a/roles/custom/matrix-synapse/molecule/default/verify.yml
+++ b/roles/custom/matrix-synapse/molecule/default/verify.yml
@@ -27,6 +27,21 @@
         file: "{{ lookup('env', 'MOLECULE_PROJECT_DIRECTORY') }}/defaults/main.yml"
         name: matrix_synapse_role_defaults
 
+    - name: Load the role's vars under a separate name
+      ansible.builtin.include_vars:
+        file: "{{ lookup('env', 'MOLECULE_PROJECT_DIRECTORY') }}/vars/main.yml"
+        name: matrix_synapse_role_vars
+
+    - name: Assert the federation self-check uses the federation hostname
+      ansible.builtin.assert:
+        that:
+          - matrix_synapse_role_vars.matrix_synapse_federation_api_url_endpoint_public == 'https://federation.example.com:8448/_matrix/federation/v1/version'
+      vars:
+        matrix_playbook_ssl_enabled: true
+        matrix_server_fqn_matrix: matrix.example.com
+        matrix_server_fqn_matrix_federation: federation.example.com
+        matrix_federation_public_port: 8448
+
     - name: Wait for the Synapse service to become active
       ansible.builtin.systemd_service:
         name: matrix-synapse.service
diff --git a/roles/custom/matrix-synapse/tasks/self_check_federation_api.yml b/roles/custom/matrix-synapse/tasks/self_check_federation_api.yml
index d50098eef..a9994bc4c 100644
--- a/roles/custom/matrix-synapse/tasks/self_check_federation_api.yml
+++ b/roles/custom/matrix-synapse/tasks/self_check_federation_api.yml
@@ -22,15 +22,15 @@
 
 - name: Fail if Matrix Federation API not working
   ansible.builtin.fail:
-    msg: "Failed checking Matrix Federation API is up at `{{ matrix_server_fqn_matrix }}` (checked endpoint: `{{ matrix_synapse_federation_api_url_endpoint_public }}`). Is Synapse running? Is port {{ matrix_federation_public_port }} open in your firewall? Full error: {{ result_matrix_synapse_federation_api }}"
+    msg: "Failed checking Matrix Federation API is up at `{{ matrix_server_fqn_matrix_federation }}` (checked endpoint: `{{ matrix_synapse_federation_api_url_endpoint_public }}`). Is Synapse running? Is port {{ matrix_federation_public_port }} open in your firewall? Full error: {{ result_matrix_synapse_federation_api }}"
   when: "matrix_synapse_enabled | bool and matrix_synapse_federation_enabled | bool and (result_matrix_synapse_federation_api.failed or 'json' not in result_matrix_synapse_federation_api)"
 
 - name: Fail if Matrix Federation API unexpectedly enabled
   ansible.builtin.fail:
-    msg: "Matrix Federation API is up at `{{ matrix_server_fqn_matrix }}` (checked endpoint: `{{ matrix_synapse_federation_api_url_endpoint_public }}`) despite being disabled."
+    msg: "Matrix Federation API is up at `{{ matrix_server_fqn_matrix_federation }}` (checked endpoint: `{{ matrix_synapse_federation_api_url_endpoint_public }}`) despite being disabled."
   when: "matrix_synapse_enabled | bool and not matrix_synapse_federation_enabled | bool and not result_matrix_synapse_federation_api.failed"
 
 - name: Report working Matrix Federation API
   ansible.builtin.debug:
-    msg: "The Matrix Federation API at `{{ matrix_server_fqn_matrix }}` (checked endpoint: `{{ matrix_synapse_federation_api_url_endpoint_public }}`) is working"
+    msg: "The Matrix Federation API at `{{ matrix_server_fqn_matrix_federation }}` (checked endpoint: `{{ matrix_synapse_federation_api_url_endpoint_public }}`) is working"
   when: "matrix_synapse_enabled | bool and matrix_synapse_federation_enabled | bool"
diff --git a/roles/custom/matrix-synapse/vars/main.yml b/roles/custom/matrix-synapse/vars/main.yml
index af5aec1dc..2d2a6bda0 100644
--- a/roles/custom/matrix-synapse/vars/main.yml
+++ b/roles/custom/matrix-synapse/vars/main.yml
@@ -9,7 +9,7 @@
 ---
 
 matrix_synapse_client_api_url_endpoint_public: "{{ 'https' if matrix_playbook_ssl_enabled else 'http' }}://{{ matrix_server_fqn_matrix }}/_matrix/client/versions"
-matrix_synapse_federation_api_url_endpoint_public: "{{ 'https' if matrix_playbook_ssl_enabled else 'http' }}://{{ matrix_server_fqn_matrix }}:{{ matrix_federation_public_port }}/_matrix/federation/v1/version"
+matrix_synapse_federation_api_url_endpoint_public: "{{ 'https' if matrix_playbook_ssl_enabled else 'http' }}://{{ matrix_server_fqn_matrix_federation }}:{{ matrix_federation_public_port }}/_matrix/federation/v1/version"
 
 matrix_synapse_media_store_directory_name: "{{ matrix_synapse_media_store_path | basename }}"