diff --git a/requirements.in b/requirements.in
index d9b0f0cb5..aaed230aa 100644
--- a/requirements.in
+++ b/requirements.in
@@ -31,7 +31,7 @@ notifications-python-client==6.3.0
 # PaaS
 awscli-cwlogs==1.4.6
 
-notifications-utils @ git+https://github.com/alphagov/notifications-utils.git@53.0.0
+notifications-utils @ git+https://github.com/alphagov/notifications-utils.git@55.1.4
 
 # gds-metrics requires prometheseus 0.2.0, override that requirement as 0.7.1 brings significant performance gains
 prometheus-client==0.10.1
diff --git a/requirements.txt b/requirements.txt
index 58ab4faed..f6ce62028 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -11,9 +11,7 @@ amqp==5.0.9
 attrs==21.2.0
     # via jsonschema
 awscli==1.21.4
-    # via
-    #   awscli-cwlogs
-    #   notifications-utils
+    # via awscli-cwlogs
 awscli-cwlogs==1.4.6
     # via -r requirements.in
 bcrypt==3.2.0
@@ -148,7 +146,7 @@ mistune==0.8.4
     # via notifications-utils
 notifications-python-client==6.3.0
     # via -r requirements.in
-notifications-utils @ git+https://github.com/alphagov/notifications-utils.git@53.0.0
+notifications-utils @ git+https://github.com/alphagov/notifications-utils.git@55.1.4
     # via -r requirements.in
 orderedset==2.0.3
     # via notifications-utils