diff --git a/requirements.txt b/requirements.txt
index 1005181b1..837b2333b 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -21,4 +21,4 @@ notifications-python-client==4.6.0
 awscli==1.14.2
 awscli-cwlogs>=1.4,<1.5
 
-git+https://github.com/alphagov/notifications-utils.git@23.1.0#egg=notifications-utils==23.1.0
+git+https://github.com/alphagov/notifications-utils.git@23.3.1#egg=notifications-utils==23.3.1