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 9d840e318a..da288e5d53 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 @@
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-    <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 fecce59252..e28e870a02 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 @@
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     <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" />
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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 fc31847651..ac10c5bbe3 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 @@
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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 1622e2d0ec..a240090260 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 @@
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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 ffa9dafe47..c84284684f 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 @@
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+    <PackageReference Include="FluentAssertions" Version="6.1.0" />
     <PackageReference Include="xunit" Version="2.4.1" />
   </ItemGroup>