diff --git a/Octokit.Tests/Octokit.Tests.csproj b/Octokit.Tests/Octokit.Tests.csproj
index c1725997..ffb62e3d 100644
--- a/Octokit.Tests/Octokit.Tests.csproj
+++ b/Octokit.Tests/Octokit.Tests.csproj
@@ -29,7 +29,7 @@
     <ProjectReference Include="..\Octokit\Octokit.csproj" />
     <ProjectReference Include="..\Octokit.Reactive\Octokit.Reactive.csproj" />
     <ProjectReference Include="..\Octokit.AsyncPaginationExtension\Octokit.AsyncPaginationExtension.csproj" />
-    <PackageReference Include="NSubstitute" Version="5.0.0" />
+    <PackageReference Include="NSubstitute" Version="5.1.0" />
   </ItemGroup>
 
   <ItemGroup>