diff --git a/.github/workflows/swift.yml b/.github/workflows/swift.yml
index 9652d5d1..44387a32 100644
--- a/.github/workflows/swift.yml
+++ b/.github/workflows/swift.yml
@@ -17,7 +17,7 @@ on:
         description: release
 
 env:
-  VERSION: 5.1.0
+  VERSION: 5.1.1
 
 jobs:
 
@@ -97,4 +97,4 @@ jobs:
         COCOAPODS_VERSION: '1.15.2'
       run: |
         gem install cocoapods -v $COCOAPODS_VERSION
-        Scripts/run_release.sh
+        Scripts/run_release.sh
\ No newline at end of file
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1c9af189..fae41347 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,11 @@
 # Optimizely Swift SDK Changelog
 
+## 5.1.1
+Jun 2th, 2025
+
+### Functionality Enhancement
+* Add experiment id and variation id added into decision notification payload ([#589](https://github.com/optimizely/swift-sdk/pull/589)).
+
 ## 5.1.0
 February 4th, 2025
 
diff --git a/OptimizelySwiftSDK.podspec b/OptimizelySwiftSDK.podspec
index 14d38f88..22790261 100644
--- a/OptimizelySwiftSDK.podspec
+++ b/OptimizelySwiftSDK.podspec
@@ -1,7 +1,7 @@
 Pod::Spec.new do |s|
   s.name                    = "OptimizelySwiftSDK"
   s.module_name	            = "Optimizely"
-  s.version                 = "5.1.0"
+  s.version                 = "5.1.1"
   s.summary                 = "Optimizely experiment framework for iOS/tvOS/watchOS"
   s.homepage                = "https://docs.developers.optimizely.com/experimentation/v4.0.0-full-stack/docs"
   s.license                 = { :type => "Apache License, Version 2.0", :file => "LICENSE" }
diff --git a/Package.swift b/Package.swift
index 22653f4e..24b0467a 100644
--- a/Package.swift
+++ b/Package.swift
@@ -24,5 +24,5 @@ let package = Package(
             resources: [.copy("Supporting Files/PrivacyInfo.xcprivacy")]
         )
     ],
-    swiftLanguageVersions: [.v5, .version("5.9")]
+    swiftLanguageVersions: [.v5]
 )
diff --git a/README.md b/README.md
index 826c3385..d068f006 100644
--- a/README.md
+++ b/README.md
@@ -39,7 +39,7 @@ If you have a name conflict with other swift packages when you add the Optimizel
 #### CocoaPods 
 1. Add the following lines to the _Podfile_:<pre>
 ```use_frameworks!```
-```pod 'OptimizelySwiftSDK', '~> 5.1.0'```
+```pod 'OptimizelySwiftSDK', '~> 5.1.1'```
 </pre>
 
 2. Run the following command: <pre>``` pod install ```</pre>
diff --git a/Sources/Utils/SDKVersion.swift b/Sources/Utils/SDKVersion.swift
index 1caaec32..298c7227 100644
--- a/Sources/Utils/SDKVersion.swift
+++ b/Sources/Utils/SDKVersion.swift
@@ -17,4 +17,4 @@
 /// Do not edit this field.
 /// - It is auto updated (Scripts/updated_version.sh) to reflect the current version
 /// - Do not put underscores in the name (Swiftlint can modify unexpectedly)
-let OPTIMIZELYSDKVERSION = "5.1.0"
+let OPTIMIZELYSDKVERSION = "5.1.1"