diff --git a/group_vars/matrix_servers b/group_vars/matrix_servers
index 1969df5d0..659745214 100755
--- a/group_vars/matrix_servers
+++ b/group_vars/matrix_servers
@@ -5299,8 +5299,6 @@ matrix_synapse_delayed_events_enabled: "{{ matrix_rtc_enabled }}"
 
 matrix_synapse_matrix_rtc_transports_livekit_url: "{{ matrix_livekit_jwt_service_public_url if matrix_livekit_jwt_service_enabled else '' }}"
 
-matrix_synapse_experimental_features_msc4222_enabled: "{{ matrix_rtc_enabled }}"
-
 matrix_synapse_experimental_features_msc4354_enabled: "{{ matrix_rtc_enabled }}"
 
 # Disable password authentication when delegating authentication to Matrix Authentication Service.
diff --git a/roles/custom/matrix-synapse/defaults/main.yml b/roles/custom/matrix-synapse/defaults/main.yml
index 9b6098fe5..78f1d65ea 100644
--- a/roles/custom/matrix-synapse/defaults/main.yml
+++ b/roles/custom/matrix-synapse/defaults/main.yml
@@ -16,7 +16,7 @@ matrix_synapse_enabled: true
 matrix_synapse_github_org_and_repo: element-hq/synapse
 
 # renovate: datasource=docker depName=ghcr.io/element-hq/synapse
-matrix_synapse_version: v1.163.2
+matrix_synapse_version: v1.164.0
 
 matrix_synapse_username: ''
 matrix_synapse_uid: ''
@@ -1592,14 +1592,6 @@ matrix_synapse_matrix_rtc_transports_custom: []
 # This is set automatically if you are using the playbook's MatrixRTC stack.
 matrix_synapse_matrix_rtc_transports_livekit_url: ''
 
-# Controls whether to enable the MSC4222 experimental feature (adding `state_after` to sync v2).
-#
-# Allow clients to opt-in to a change of the sync v2 API that allows them to correctly track the state of the room.
-# This is required by Element Call to track room state reliably.
-#
-# See https://github.com/matrix-org/matrix-spec-proposals/pull/4222
-matrix_synapse_experimental_features_msc4222_enabled: false
-
 # Controls whether to enable the MSC4306 experimental feature ("thread subscriptions").
 #
 # In current Synapse, this also enables the MSC4308 thread-subscriptions extension
@@ -1634,7 +1626,6 @@ matrix_synapse_experimental_features_default: |
       'msc3202_transaction_extensions': matrix_synapse_experimental_features_msc3202_transaction_extensions_enabled | bool,
       'msc4108_enabled': matrix_synapse_experimental_features_msc4108_enabled | bool,
       'msc4143_enabled': matrix_synapse_experimental_features_msc4143_enabled | bool,
-      'msc4222_enabled': matrix_synapse_experimental_features_msc4222_enabled | bool,
       'msc4306_enabled': matrix_synapse_experimental_features_msc4306_enabled | bool,
       'msc4354_enabled': matrix_synapse_experimental_features_msc4354_enabled | bool,
     }
diff --git a/roles/custom/matrix-synapse/tasks/validate_config.yml b/roles/custom/matrix-synapse/tasks/validate_config.yml
index 4e37ac2de..351389d7d 100644
--- a/roles/custom/matrix-synapse/tasks/validate_config.yml
+++ b/roles/custom/matrix-synapse/tasks/validate_config.yml
@@ -87,6 +87,7 @@
     - {'old': 'matrix_synapse_experimental_features_msc4133_enabled', 'new': '<removed - this feature is enabled by default now>'}
 
     - {'old': 'matrix_synapse_experimental_features_msc3266_enabled', 'new': '<removed - MSC3266 support was stabilized in Synapse v1.153.0 and the room summary API is now always enabled>'}
+    - {'old': 'matrix_synapse_experimental_features_msc4222_enabled', 'new': '<removed - state_after sync support is always enabled since Synapse v1.164.0; remove this variable from vars.yml>'}
     - {'old': 'matrix_synapse_experimental_features_msc4140_enabled', 'new': 'matrix_synapse_delayed_events_enabled'}
     - {'old': 'matrix_synapse_experimental_features_msc4429_enabled', 'new': '<removed - Synapse does not actually support MSC4429 in any released version, so this flag never had any effect>'}