diff --git a/NHSDigital.ApiPlatform.Sdk.AspNetCore.Tests.Unit/NHSDigital.ApiPlatform.Sdk.AspNetCore.Tests.Unit.csproj b/NHSDigital.ApiPlatform.Sdk.AspNetCore.Tests.Unit/NHSDigital.ApiPlatform.Sdk.AspNetCore.Tests.Unit.csproj
index 752f126..5d7f6e0 100644
--- a/NHSDigital.ApiPlatform.Sdk.AspNetCore.Tests.Unit/NHSDigital.ApiPlatform.Sdk.AspNetCore.Tests.Unit.csproj
+++ b/NHSDigital.ApiPlatform.Sdk.AspNetCore.Tests.Unit/NHSDigital.ApiPlatform.Sdk.AspNetCore.Tests.Unit.csproj
@@ -15,7 +15,7 @@
 			<IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
 		</PackageReference>
 		<PackageReference Include="FluentAssertions" Version="[7.2.2]" />
-		<PackageReference Include="Hl7.Fhir.STU3" Version="6.3.0" />
+		<PackageReference Include="Hl7.Fhir.STU3" Version="6.4.0" />
 		<PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.8.1" />
 		<PackageReference Include="Moq" Version="4.20.72" />
 		<PackageReference Include="Tynamix.ObjectFiller" Version="1.5.9" />
diff --git a/NHSDigital.ApiPlatform.Sdk.Tests.Unit/NHSDigital.ApiPlatform.Sdk.Tests.Unit.csproj b/NHSDigital.ApiPlatform.Sdk.Tests.Unit/NHSDigital.ApiPlatform.Sdk.Tests.Unit.csproj
index 0ffba71..b9f5681 100644
--- a/NHSDigital.ApiPlatform.Sdk.Tests.Unit/NHSDigital.ApiPlatform.Sdk.Tests.Unit.csproj
+++ b/NHSDigital.ApiPlatform.Sdk.Tests.Unit/NHSDigital.ApiPlatform.Sdk.Tests.Unit.csproj
@@ -15,7 +15,7 @@
 			<IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
 		</PackageReference>
 		<PackageReference Include="FluentAssertions" Version="[7.2.2]" />
-		<PackageReference Include="Hl7.Fhir.STU3" Version="6.3.0" />
+		<PackageReference Include="Hl7.Fhir.STU3" Version="6.4.0" />
 		<PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.8.1" />
 		<PackageReference Include="Moq" Version="4.20.72" />
 		<PackageReference Include="Tynamix.ObjectFiller" Version="1.5.9" />