diff --git a/build.gradle b/build.gradle
index 93d2cecd6..03da57861 100644
--- a/build.gradle
+++ b/build.gradle
@@ -355,7 +355,7 @@ dependencies {
   implementation group: 'net.logstash.logback', name: 'logstash-logback-encoder', version: '8.1'
 
   // send-letter-client requires upgrade but causes gradle dependency exceptions ADOP-2686
-  implementation group: 'com.github.hmcts', name: 'send-letter-client', version: '4.0.4'
+  implementation group: 'com.github.hmcts', name: 'send-letter-client', version: '5.1.1'
   implementation group: 'com.github.hmcts', name: 'service-auth-provider-java-client', version: '5.3.3'
   implementation group: 'com.github.hmcts', name: 'ccd-case-document-am-client', version: '1.59.2'