diff --git a/src/CfsAlerts.Tests/CfsAlerts.Tests.csproj b/src/CfsAlerts.Tests/CfsAlerts.Tests.csproj
index 7eb7c2b..5886eca 100644
--- a/src/CfsAlerts.Tests/CfsAlerts.Tests.csproj
+++ b/src/CfsAlerts.Tests/CfsAlerts.Tests.csproj
@@ -22,7 +22,7 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.7.0" />
     <PackageReference Include="coverlet.collector" Version="10.0.1" />
-    <PackageReference Include="NSubstitute" Version="5.3.0" />
+    <PackageReference Include="NSubstitute" Version="6.0.0" />
     <PackageReference Include="NSubstitute.Analyzers.CSharp" Version="1.0.17">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>