diff --git a/CHANGELOG.md b/CHANGELOG.md
index 549c758..d2d99c3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,4 +1,7 @@
-## 2.5.0-nullsafety.3-dev
+## 2.5.0-nullsafety.3
+
+* Update SDK constraints to `>=2.12.0-0 <3.0.0` based on beta release
+  guidelines.
 
 ## 2.5.0-nullsafety.2
 
diff --git a/pubspec.yaml b/pubspec.yaml
index 5f87f9b..3aa8080 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,12 +1,11 @@
 name: async
-version: 2.5.0-nullsafety.3-dev
+version: 2.5.0-nullsafety.3
 
 description: Utility functions and classes related to the 'dart:async' library.
 homepage: https://www.github.com/dart-lang/async
 
 environment:
-  # This must remain a tight constraint until nnbd is stable
-  sdk: '>=2.10.0-0 <2.12.0'
+  sdk: ">=2.12.0-0 <3.0.0"
 
 dependencies:
   collection: '>=1.15.0-nullsafety <1.15.0'