diff --git a/tests/Fl.Functional.Utils.Tests/Fl.Functional.Utils.Tests.csproj b/tests/Fl.Functional.Utils.Tests/Fl.Functional.Utils.Tests.csproj
index 70140db..fd7fcb9 100644
--- a/tests/Fl.Functional.Utils.Tests/Fl.Functional.Utils.Tests.csproj
+++ b/tests/Fl.Functional.Utils.Tests/Fl.Functional.Utils.Tests.csproj
@@ -11,7 +11,7 @@
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     </PackageReference>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.7.0" />
-    <PackageReference Include="NSubstitute" Version="5.3.0" />
+    <PackageReference Include="NSubstitute" Version="6.0.0" />
     <PackageReference Include="NUnit" Version="4.6.1" />
     <PackageReference Include="NUnit3TestAdapter" Version="6.2.0" />
     <PackageReference Include="coverlet.collector" Version="10.0.1">