diff --git a/tests/Prometheus.Client.MetricPusher.HostedService.Tests.csproj b/tests/Prometheus.Client.MetricPusher.HostedService.Tests.csproj
index 367da5d..acc4ba0 100644
--- a/tests/Prometheus.Client.MetricPusher.HostedService.Tests.csproj
+++ b/tests/Prometheus.Client.MetricPusher.HostedService.Tests.csproj
@@ -7,7 +7,7 @@
   <ItemGroup>
     <PackageReference Include="FluentAssertions" Version="6.12.1" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.11.1" />
-    <PackageReference Include="NSubstitute" Version="5.1.0" />
+    <PackageReference Include="NSubstitute" Version="5.3.0" />
     <PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="6.0.1" />
     <PackageReference Include="xunit" Version="2.9.2" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.8.2">