diff --git a/CHANGELOG.md b/CHANGELOG.md
index a2c1dfb..7f8ed60 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,8 @@
+## 1.2.0-nullsafety.3
+
+* Update SDK constraints to `>=2.12.0-0 <3.0.0` based on beta release
+  guidelines.
+
 ## 1.2.0-nullsafety.2
 
 * Allow prerelease versions of the 2.12 sdk.
diff --git a/pubspec.yaml b/pubspec.yaml
index 148db8d..f4a49e8 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,12 +1,11 @@
 name: term_glyph
-version: 1.2.0-nullsafety.2
+version: 1.2.0-nullsafety.3
 
 description: Useful Unicode glyphs and ASCII substitutes.
 homepage: https://github.com/dart-lang/term_glyph
 
 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"
 
 dev_dependencies:
   csv: '>=3.0.0 <5.0.0'