diff --git a/.ruby-version b/.ruby-version
index bea438e9..47b322c9 100644
--- a/.ruby-version
+++ b/.ruby-version
@@ -1 +1 @@
-3.3.1
+3.4.1
diff --git a/Dockerfile b/Dockerfile
index aebc03e3..a5efa3a0 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-ARG ruby_version=3.3
+ARG ruby_version=3.4
 ARG base_image=ghcr.io/alphagov/govuk-ruby-base:$ruby_version
 ARG builder_image=ghcr.io/alphagov/govuk-ruby-builder:$ruby_version
 
diff --git a/Gemfile.lock b/Gemfile.lock
index 7607256a..cc92b1c3 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -692,4 +692,4 @@ DEPENDENCIES
   webmock
 
 BUNDLED WITH
-   2.5.9
+   2.6.2