diff --git a/Directory.Packages.props b/Directory.Packages.props
index 4977685dcd0..2cd6bc1659e 100644
--- a/Directory.Packages.props
+++ b/Directory.Packages.props
@@ -8,6 +8,8 @@
     <CentralPackageTransitivePinningEnabled>true</CentralPackageTransitivePinningEnabled>
     <TestcontainersPackageVersion>4.0.0</TestcontainersPackageVersion>
     <AzureProvisiongVersion>1.0.0</AzureProvisiongVersion>
+    <!-- The Npgsql version used when using Npgsql EF Core on net8. The major versions need to match between Npgsql and EF Core. -->
+    <Npgsql8Version>8.0.6</Npgsql8Version>
   </PropertyGroup>
   <ItemGroup>
     <!-- Azure SDK for .NET dependencies -->
diff --git a/playground/PostgresEndToEnd/PostgresEndToEnd.ApiService/PostgresEndToEnd.ApiService.csproj b/playground/PostgresEndToEnd/PostgresEndToEnd.ApiService/PostgresEndToEnd.ApiService.csproj
index 8f86dcecdbf..fd83be35ebb 100644
--- a/playground/PostgresEndToEnd/PostgresEndToEnd.ApiService/PostgresEndToEnd.ApiService.csproj
+++ b/playground/PostgresEndToEnd/PostgresEndToEnd.ApiService/PostgresEndToEnd.ApiService.csproj
@@ -8,6 +8,9 @@
 
   <ItemGroup>
     <AspireProjectOrPackageReference Include="Aspire.Npgsql.EntityFrameworkCore.PostgreSQL" />
+    <!-- Npgsql EF needs to match the same major version as the underlying Npgsql assemblies. -->
+    <PackageReference Include="Npgsql.DependencyInjection" VersionOverride="$(Npgsql8Version)" />
+    <PackageReference Include="Npgsql.OpenTelemetry" VersionOverride="$(Npgsql8Version)" />
     <ProjectReference Include="..\..\Playground.ServiceDefaults\Playground.ServiceDefaults.csproj" />
   </ItemGroup>
 
diff --git a/playground/TestShop/CatalogDb/CatalogDb.csproj b/playground/TestShop/CatalogDb/CatalogDb.csproj
index bb67086d13c..1f1e0c39969 100644
--- a/playground/TestShop/CatalogDb/CatalogDb.csproj
+++ b/playground/TestShop/CatalogDb/CatalogDb.csproj
@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk.Web">
+<Project Sdk="Microsoft.NET.Sdk.Web">
 
   <PropertyGroup>
     <TargetFramework>$(DefaultTargetFramework)</TargetFramework>
@@ -13,6 +13,10 @@
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
+
+    <!-- Npgsql EF needs to match the same major version as the underlying Npgsql assemblies. -->
+    <PackageReference Include="Npgsql.DependencyInjection" VersionOverride="$(Npgsql8Version)" />
+    <PackageReference Include="Npgsql.OpenTelemetry" VersionOverride="$(Npgsql8Version)" />
   </ItemGroup>
   
 </Project>
diff --git a/playground/TestShop/CatalogModel/CatalogModel.csproj b/playground/TestShop/CatalogModel/CatalogModel.csproj
index c0d379eb9f1..afc8b1ff55e 100644
--- a/playground/TestShop/CatalogModel/CatalogModel.csproj
+++ b/playground/TestShop/CatalogModel/CatalogModel.csproj
@@ -6,12 +6,11 @@
     <Nullable>enable</Nullable>
   </PropertyGroup>
 
-  <ItemGroup>
-    <PackageReference Include="Npgsql.EntityFrameworkCore.PostgreSQL" />
-  </ItemGroup>
-
   <ItemGroup>
     <AspireProjectOrPackageReference Include="Aspire.Npgsql.EntityFrameworkCore.PostgreSQL" />
+    <!-- Npgsql EF needs to match the same major version as the underlying Npgsql assemblies. -->
+    <PackageReference Include="Npgsql.DependencyInjection" VersionOverride="$(Npgsql8Version)" />
+    <PackageReference Include="Npgsql.OpenTelemetry" VersionOverride="$(Npgsql8Version)" />
   </ItemGroup>
 
 </Project>
diff --git a/playground/TestShop/CatalogService/CatalogService.csproj b/playground/TestShop/CatalogService/CatalogService.csproj
index 544e4e8b059..55200d3bc11 100644
--- a/playground/TestShop/CatalogService/CatalogService.csproj
+++ b/playground/TestShop/CatalogService/CatalogService.csproj
@@ -13,13 +13,13 @@
     <Content Include="Images\**\*" CopyToOutputDirectory="PreserveNewest" CopyToPublishDirectory="PreserveNewest" ExcludeFromSingleFile="true" />
   </ItemGroup>
 
-  <ItemGroup>
-    <PackageReference Include="Npgsql.EntityFrameworkCore.PostgreSQL" />
-  </ItemGroup>
-
   <ItemGroup>
     <ProjectReference Include="..\CatalogModel\CatalogModel.csproj" />
     <ProjectReference Include="..\TestShop.ServiceDefaults\TestShop.ServiceDefaults.csproj" />
+
+    <!-- Npgsql EF needs to match the same major version as the underlying Npgsql assemblies. -->
+    <PackageReference Include="Npgsql.DependencyInjection" VersionOverride="$(Npgsql8Version)" />
+    <PackageReference Include="Npgsql.OpenTelemetry" VersionOverride="$(Npgsql8Version)" />
   </ItemGroup>
 
 </Project>
diff --git a/playground/bicep/BicepSample.ApiService/BicepSample.ApiService.csproj b/playground/bicep/BicepSample.ApiService/BicepSample.ApiService.csproj
index 39548f80adc..0e17b4fe68e 100644
--- a/playground/bicep/BicepSample.ApiService/BicepSample.ApiService.csproj
+++ b/playground/bicep/BicepSample.ApiService/BicepSample.ApiService.csproj
@@ -14,6 +14,9 @@
     <AspireProjectOrPackageReference Include="Aspire.Microsoft.Azure.Cosmos" />
     <AspireProjectOrPackageReference Include="Aspire.Microsoft.EntityFrameworkCore.SqlServer" />
     <AspireProjectOrPackageReference Include="Aspire.Npgsql.EntityFrameworkCore.PostgreSQL" />
+    <!-- Npgsql EF needs to match the same major version as the underlying Npgsql assemblies. -->
+    <PackageReference Include="Npgsql.DependencyInjection" VersionOverride="$(Npgsql8Version)" />
+    <PackageReference Include="Npgsql.OpenTelemetry" VersionOverride="$(Npgsql8Version)" />
     <AspireProjectOrPackageReference Include="Aspire.StackExchange.Redis" />
     <ProjectReference Include="..\..\Playground.ServiceDefaults\Playground.ServiceDefaults.csproj" />
   </ItemGroup>
diff --git a/playground/cdk/CdkSample.ApiService/CdkSample.ApiService.csproj b/playground/cdk/CdkSample.ApiService/CdkSample.ApiService.csproj
index d2552ed1579..54c91f50975 100644
--- a/playground/cdk/CdkSample.ApiService/CdkSample.ApiService.csproj
+++ b/playground/cdk/CdkSample.ApiService/CdkSample.ApiService.csproj
@@ -14,6 +14,9 @@
     <AspireProjectOrPackageReference Include="Aspire.Microsoft.EntityFrameworkCore.Cosmos" />
     <AspireProjectOrPackageReference Include="Aspire.Microsoft.EntityFrameworkCore.SqlServer" />
     <AspireProjectOrPackageReference Include="Aspire.Npgsql.EntityFrameworkCore.PostgreSQL" />
+    <!-- Npgsql EF needs to match the same major version as the underlying Npgsql assemblies. -->
+    <PackageReference Include="Npgsql.DependencyInjection" VersionOverride="$(Npgsql8Version)" />
+    <PackageReference Include="Npgsql.OpenTelemetry" VersionOverride="$(Npgsql8Version)" />
     <AspireProjectOrPackageReference Include="Aspire.StackExchange.Redis" />
     <ProjectReference Include="..\..\Playground.ServiceDefaults\Playground.ServiceDefaults.csproj" />
 
diff --git a/playground/waitfor/WaitForSandbox.ApiService/WaitForSandbox.ApiService.csproj b/playground/waitfor/WaitForSandbox.ApiService/WaitForSandbox.ApiService.csproj
index 1ae39c8c4bb..5192cb3b1b7 100644
--- a/playground/waitfor/WaitForSandbox.ApiService/WaitForSandbox.ApiService.csproj
+++ b/playground/waitfor/WaitForSandbox.ApiService/WaitForSandbox.ApiService.csproj
@@ -8,6 +8,9 @@
 
   <ItemGroup>
     <AspireProjectOrPackageReference Include="Aspire.Npgsql.EntityFrameworkCore.PostgreSQL" />
+    <!-- Npgsql EF needs to match the same major version as the underlying Npgsql assemblies. -->
+    <PackageReference Include="Npgsql.DependencyInjection" VersionOverride="$(Npgsql8Version)" />
+    <PackageReference Include="Npgsql.OpenTelemetry" VersionOverride="$(Npgsql8Version)" />
     <ProjectReference Include="..\..\Playground.ServiceDefaults\Playground.ServiceDefaults.csproj" />
     <ProjectReference Include="..\WaitForSandbox.Common\WaitForSandbox.Common.csproj" />
   </ItemGroup>
diff --git a/playground/waitfor/WaitForSandbox.DbSetup/WaitForSandbox.DbSetup.csproj b/playground/waitfor/WaitForSandbox.DbSetup/WaitForSandbox.DbSetup.csproj
index aa06176671b..70678f72057 100644
--- a/playground/waitfor/WaitForSandbox.DbSetup/WaitForSandbox.DbSetup.csproj
+++ b/playground/waitfor/WaitForSandbox.DbSetup/WaitForSandbox.DbSetup.csproj
@@ -9,6 +9,9 @@
 
   <ItemGroup>
     <ProjectReference Include="..\..\..\src\Components\Aspire.Npgsql.EntityFrameworkCore.PostgreSQL\Aspire.Npgsql.EntityFrameworkCore.PostgreSQL.csproj" />
+    <!-- Npgsql EF needs to match the same major version as the underlying Npgsql assemblies. -->
+    <PackageReference Include="Npgsql.DependencyInjection" VersionOverride="$(Npgsql8Version)" />
+    <PackageReference Include="Npgsql.OpenTelemetry" VersionOverride="$(Npgsql8Version)" />
     <ProjectReference Include="..\WaitForSandbox.Common\WaitForSandbox.Common.csproj" />
   </ItemGroup>
 
diff --git a/src/Components/Aspire.Npgsql.EntityFrameworkCore.PostgreSQL/Aspire.Npgsql.EntityFrameworkCore.PostgreSQL.csproj b/src/Components/Aspire.Npgsql.EntityFrameworkCore.PostgreSQL/Aspire.Npgsql.EntityFrameworkCore.PostgreSQL.csproj
index cbf70e19baf..443b08f4036 100644
--- a/src/Components/Aspire.Npgsql.EntityFrameworkCore.PostgreSQL/Aspire.Npgsql.EntityFrameworkCore.PostgreSQL.csproj
+++ b/src/Components/Aspire.Npgsql.EntityFrameworkCore.PostgreSQL/Aspire.Npgsql.EntityFrameworkCore.PostgreSQL.csproj
@@ -34,8 +34,8 @@
 
   <!-- Npgsql EF needs to match the same major version as the underlying Npgsql assemblies. -->
   <ItemGroup Condition="'$(TargetFramework)' == 'net8.0'">
-    <PackageReference Update="Npgsql.DependencyInjection" VersionOverride="8.0.6" />
-    <PackageReference Update="Npgsql.OpenTelemetry" VersionOverride="8.0.6" />
+    <PackageReference Update="Npgsql.DependencyInjection" VersionOverride="$(Npgsql8Version)" />
+    <PackageReference Update="Npgsql.OpenTelemetry" VersionOverride="$(Npgsql8Version)" />
   </ItemGroup>
 
 </Project>
diff --git a/tests/Aspire.Npgsql.EntityFrameworkCore.PostgreSQL.Tests/Aspire.Npgsql.EntityFrameworkCore.PostgreSQL.Tests.csproj b/tests/Aspire.Npgsql.EntityFrameworkCore.PostgreSQL.Tests/Aspire.Npgsql.EntityFrameworkCore.PostgreSQL.Tests.csproj
index 0bd9a1debd9..3e5a39c442f 100644
--- a/tests/Aspire.Npgsql.EntityFrameworkCore.PostgreSQL.Tests/Aspire.Npgsql.EntityFrameworkCore.PostgreSQL.Tests.csproj
+++ b/tests/Aspire.Npgsql.EntityFrameworkCore.PostgreSQL.Tests/Aspire.Npgsql.EntityFrameworkCore.PostgreSQL.Tests.csproj
@@ -18,8 +18,8 @@
 
   <!-- Npgsql EF needs to match the same major version as the underlying Npgsql assemblies. -->
   <ItemGroup Condition="'$(TargetFramework)' == 'net8.0'">
-    <PackageReference Include="Npgsql.DependencyInjection" VersionOverride="8.0.6" />
-    <PackageReference Include="Npgsql.OpenTelemetry" VersionOverride="8.0.6" />
+    <PackageReference Include="Npgsql.DependencyInjection" VersionOverride="$(Npgsql8Version)" />
+    <PackageReference Include="Npgsql.OpenTelemetry" VersionOverride="$(Npgsql8Version)" />
   </ItemGroup>
 
 </Project>