diff --git a/packages/artifact_proxy/pubspec.yaml b/packages/artifact_proxy/pubspec.yaml
index ec2bf9dd..c90d2102 100644
--- a/packages/artifact_proxy/pubspec.yaml
+++ b/packages/artifact_proxy/pubspec.yaml
@@ -6,7 +6,7 @@ publish_to: "none"
 resolution: workspace
 
 environment:
-  sdk: ">=3.8.0 <4.0.0"
+  sdk: ">=3.9.0 <4.0.0"
 
 dependencies:
   checked_yaml: ^2.0.4
diff --git a/packages/discord_gcp_alerts/pubspec.yaml b/packages/discord_gcp_alerts/pubspec.yaml
index 462f0cef..3fb6d971 100644
--- a/packages/discord_gcp_alerts/pubspec.yaml
+++ b/packages/discord_gcp_alerts/pubspec.yaml
@@ -5,7 +5,7 @@ publish_to: none
 resolution: workspace
 
 environment:
-  sdk: ">=3.8.0 <4.0.0"
+  sdk: ">=3.9.0 <4.0.0"
 
 dependencies:
   http: ^1.5.0
diff --git a/packages/jwt/pubspec.yaml b/packages/jwt/pubspec.yaml
index 73a87468..3847c43b 100644
--- a/packages/jwt/pubspec.yaml
+++ b/packages/jwt/pubspec.yaml
@@ -5,7 +5,7 @@ publish_to: none
 resolution: workspace
 
 environment:
-  sdk: ">=3.8.0 <4.0.0"
+  sdk: ">=3.9.0 <4.0.0"
 
 dependencies:
   clock: ^1.1.0
diff --git a/packages/redis_client/pubspec.yaml b/packages/redis_client/pubspec.yaml
index d38ef038..8b910fc7 100644
--- a/packages/redis_client/pubspec.yaml
+++ b/packages/redis_client/pubspec.yaml
@@ -7,7 +7,7 @@ topics: [redis, cache, shorebird]
 resolution: workspace
 
 environment:
-  sdk: ">=3.8.0 <4.0.0"
+  sdk: ">=3.9.0 <4.0.0"
 
 dependencies:
   resp_client: ^1.2.0
diff --git a/packages/scoped_deps/pubspec.yaml b/packages/scoped_deps/pubspec.yaml
index 2c8d22ec..b235bc4a 100644
--- a/packages/scoped_deps/pubspec.yaml
+++ b/packages/scoped_deps/pubspec.yaml
@@ -6,7 +6,7 @@ repository: https://github.com/shorebirdtech/shorebird/tree/main/packages/scoped
 resolution: workspace
 
 environment:
-  sdk: ">=3.8.0 <4.0.0"
+  sdk: ">=3.9.0 <4.0.0"
 
 dependencies:
   meta: ^1.0.0
diff --git a/packages/shorebird_cli/pubspec.yaml b/packages/shorebird_cli/pubspec.yaml
index 105d70a3..dbb4f106 100644
--- a/packages/shorebird_cli/pubspec.yaml
+++ b/packages/shorebird_cli/pubspec.yaml
@@ -7,7 +7,7 @@ resolution: workspace
 publish_to: none
 
 environment:
-  sdk: ">=3.8.0 <4.0.0"
+  sdk: ">=3.9.0 <4.0.0"
 
 dependencies:
   archive: ^4.0.7
diff --git a/packages/shorebird_code_push_client/pubspec.yaml b/packages/shorebird_code_push_client/pubspec.yaml
index 623a59b1..9ae0eb93 100644
--- a/packages/shorebird_code_push_client/pubspec.yaml
+++ b/packages/shorebird_code_push_client/pubspec.yaml
@@ -7,7 +7,7 @@ resolution: workspace
 publish_to: none
 
 environment:
-  sdk: ">=3.8.0 <4.0.0"
+  sdk: ">=3.9.0 <4.0.0"
 
 dependencies:
   collection: ^1.18.0
diff --git a/packages/shorebird_code_push_protocol/pubspec.yaml b/packages/shorebird_code_push_protocol/pubspec.yaml
index 515f77a0..55a56bed 100644
--- a/packages/shorebird_code_push_protocol/pubspec.yaml
+++ b/packages/shorebird_code_push_protocol/pubspec.yaml
@@ -7,7 +7,7 @@ resolution: workspace
 publish_to: none
 
 environment:
-  sdk: ">=3.8.0 <4.0.0"
+  sdk: ">=3.9.0 <4.0.0"
 
 dependencies:
   decimal: ^3.2.4
diff --git a/packages/stripe_api/pubspec.yaml b/packages/stripe_api/pubspec.yaml
index ea4b85c5..aa22f312 100644
--- a/packages/stripe_api/pubspec.yaml
+++ b/packages/stripe_api/pubspec.yaml
@@ -5,7 +5,7 @@ publish_to: none
 resolution: workspace
 
 environment:
-  sdk: ">=3.8.0 <4.0.0"
+  sdk: ">=3.9.0 <4.0.0"
 
 dependencies:
   collection: ^1.17.1