diff --git a/Gemfile b/Gemfile
index 4d063ba..c8655eb 100644
--- a/Gemfile
+++ b/Gemfile
@@ -5,7 +5,7 @@ gem "bootsnap", require: false
 gem "erubis", "2.7.0"
 gem "govuk_app_config", "~> 9.14.3"
 gem "nokogiri", "1.16.7"
-gem "optic14n", "2.1.0" # Ideally version should be synced with Transition
+gem "optic14n", "3.0.0" # Ideally version should be synced with Transition
 gem "pg"
 gem "rack", "~> 3.1.8"
 gem "rake", "13.2.1"
diff --git a/Gemfile.lock b/Gemfile.lock
index 18d91c1..bbecfdd 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -315,7 +315,7 @@ GEM
       opentelemetry-semantic_conventions
     opentelemetry-semantic_conventions (1.10.1)
       opentelemetry-api (~> 1.0)
-    optic14n (2.1.0)
+    optic14n (3.0.0)
       addressable (~> 2.7)
     parallel (1.26.3)
     parser (3.3.4.2)
@@ -461,7 +461,7 @@ DEPENDENCIES
   govuk_app_config (~> 9.14.3)
   mr-sparkle (= 0.3.0)
   nokogiri (= 1.16.7)
-  optic14n (= 2.1.0)
+  optic14n (= 3.0.0)
   pg
   pry
   rack (~> 3.1.8)