diff --git a/src/Tests/UnitTests/NClap.Tests.csproj b/src/Tests/UnitTests/NClap.Tests.csproj
index fc2ec81..2d73cb5 100644
--- a/src/Tests/UnitTests/NClap.Tests.csproj
+++ b/src/Tests/UnitTests/NClap.Tests.csproj
@@ -23,7 +23,7 @@
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.7.2" />
     <PackageReference Include="MSTest.TestAdapter" Version="3.1.1" />
     <PackageReference Include="MSTest.TestFramework" Version="3.1.1" />
-    <PackageReference Include="NSubstitute" Version="5.0.0" />
+    <PackageReference Include="NSubstitute" Version="5.1.0" />
   </ItemGroup>
   
   <ItemGroup>