diff --git a/test/Riok.Mapperly.IntegrationTests/Riok.Mapperly.IntegrationTests.csproj b/test/Riok.Mapperly.IntegrationTests/Riok.Mapperly.IntegrationTests.csproj
index a3f260bdd9..415290ea2c 100644
--- a/test/Riok.Mapperly.IntegrationTests/Riok.Mapperly.IntegrationTests.csproj
+++ b/test/Riok.Mapperly.IntegrationTests/Riok.Mapperly.IntegrationTests.csproj
@@ -43,7 +43,7 @@
   <!-- cannot use source generated polyfills since they require language version 11 -->
   <ItemGroup Condition="'$(TargetFramework)' == 'net48'">
     <PackageReference Include="System.Collections.Immutable" Version="8.0.0" />
-    <PackageReference Include="Portable.System.DateTimeOnly" Version="7.0.1" />
+    <PackageReference Include="Portable.System.DateTimeOnly" Version="8.0.0" />
     <PackageReference Include="IsExternalInit" Version="1.0.3">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers</IncludeAssets>