diff --git a/Ix.NET/Source/System.Interactive.Async.Providers.Tests/System.Interactive.Async.Providers.Tests.csproj b/Ix.NET/Source/System.Interactive.Async.Providers.Tests/System.Interactive.Async.Providers.Tests.csproj
index 9d840e318..da288e5d5 100644
--- a/Ix.NET/Source/System.Interactive.Async.Providers.Tests/System.Interactive.Async.Providers.Tests.csproj
+++ b/Ix.NET/Source/System.Interactive.Async.Providers.Tests/System.Interactive.Async.Providers.Tests.csproj
@@ -22,7 +22,7 @@
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
-    <PackageReference Include="FluentAssertions" Version="5.10.3" />
+    <PackageReference Include="FluentAssertions" Version="6.1.0" />
     <PackageReference Include="xunit" Version="2.4.1" />
   </ItemGroup>
 
diff --git a/Ix.NET/Source/System.Interactive.Async.Tests/System.Interactive.Async.Tests.csproj b/Ix.NET/Source/System.Interactive.Async.Tests/System.Interactive.Async.Tests.csproj
index fecce5925..e28e870a0 100644
--- a/Ix.NET/Source/System.Interactive.Async.Tests/System.Interactive.Async.Tests.csproj
+++ b/Ix.NET/Source/System.Interactive.Async.Tests/System.Interactive.Async.Tests.csproj
@@ -19,7 +19,7 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.10.0" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.4.3" />
-    <PackageReference Include="FluentAssertions" Version="5.10.3" />
+    <PackageReference Include="FluentAssertions" Version="6.1.0" />
     <PackageReference Include="xunit" Version="2.4.1" />
   </ItemGroup>
 
diff --git a/Ix.NET/Source/System.Interactive.Tests/System.Interactive.Tests.csproj b/Ix.NET/Source/System.Interactive.Tests/System.Interactive.Tests.csproj
index fc3184765..ac10c5bbe 100644
--- a/Ix.NET/Source/System.Interactive.Tests/System.Interactive.Tests.csproj
+++ b/Ix.NET/Source/System.Interactive.Tests/System.Interactive.Tests.csproj
@@ -21,7 +21,7 @@
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
-    <PackageReference Include="FluentAssertions" Version="5.10.3" />
+    <PackageReference Include="FluentAssertions" Version="6.1.0" />
     <PackageReference Include="xunit" Version="2.4.1" />
   </ItemGroup>
 
diff --git a/Ix.NET/Source/System.Linq.Async.Queryable.Tests/System.Linq.Async.Queryable.Tests.csproj b/Ix.NET/Source/System.Linq.Async.Queryable.Tests/System.Linq.Async.Queryable.Tests.csproj
index 1622e2d0e..a24009026 100644
--- a/Ix.NET/Source/System.Linq.Async.Queryable.Tests/System.Linq.Async.Queryable.Tests.csproj
+++ b/Ix.NET/Source/System.Linq.Async.Queryable.Tests/System.Linq.Async.Queryable.Tests.csproj
@@ -19,7 +19,7 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.10.0" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.4.3" />
-    <PackageReference Include="FluentAssertions" Version="5.10.3" />
+    <PackageReference Include="FluentAssertions" Version="6.1.0" />
     <PackageReference Include="xunit" Version="2.4.1" />
   </ItemGroup>
 
diff --git a/Ix.NET/Source/System.Linq.Async.Tests/System.Linq.Async.Tests.csproj b/Ix.NET/Source/System.Linq.Async.Tests/System.Linq.Async.Tests.csproj
index ffa9dafe4..c84284684 100644
--- a/Ix.NET/Source/System.Linq.Async.Tests/System.Linq.Async.Tests.csproj
+++ b/Ix.NET/Source/System.Linq.Async.Tests/System.Linq.Async.Tests.csproj
@@ -41,7 +41,7 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.10.0" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.4.3" />
-    <PackageReference Include="FluentAssertions" Version="5.10.3" />
+    <PackageReference Include="FluentAssertions" Version="6.1.0" />
     <PackageReference Include="xunit" Version="2.4.1" />
   </ItemGroup>