diff --git a/test/BlazorMerge.UnitTests/BlazorMerge.UnitTests.csproj b/test/BlazorMerge.UnitTests/BlazorMerge.UnitTests.csproj
index dee6ad7..72c020e 100644
--- a/test/BlazorMerge.UnitTests/BlazorMerge.UnitTests.csproj
+++ b/test/BlazorMerge.UnitTests/BlazorMerge.UnitTests.csproj
@@ -13,7 +13,7 @@
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-      <PackageReference Include="NSubstitute" Version="5.3.0" />
+      <PackageReference Include="NSubstitute" Version="6.0.0" />
       <PackageReference Include="StubLogger" Version="3.0.1.9" />
       <PackageReference Include="Verify.XunitV3" Version="31.21.0" />
       <PackageReference Include="xunit.runner.visualstudio" Version="3.1.5">