diff --git a/src/Hyperledger.Aries/Hyperledger.Aries.csproj b/src/Hyperledger.Aries/Hyperledger.Aries.csproj
index b56d1af1..0deebcc2 100644
--- a/src/Hyperledger.Aries/Hyperledger.Aries.csproj
+++ b/src/Hyperledger.Aries/Hyperledger.Aries.csproj
@@ -19,7 +19,7 @@
         <PackageReference Include="Polly" Version="$(PollyVersion)" />
         <PackageReference Include="Portable.BouncyCastle" Version="1.9.0" />
         <PackageReference Include="Stateless" Version="$(StatelessVersion)" />
-        <PackageReference Include="System.Collections.Immutable" Version="1.7.1" />
+        <PackageReference Include="System.Collections.Immutable" Version="9.0.0" />
         <PackageReference Include="System.IdentityModel.Tokens.Jwt" Version="6.25.1" />
         <PackageReference Include="System.Reactive.Linq" Version="$(SystemReactiveLinqVersion)" />
     </ItemGroup>