diff --git a/src/Taxjar/Taxjar.csproj b/src/Taxjar/Taxjar.csproj
index 51576b5..df00b8b 100644
--- a/src/Taxjar/Taxjar.csproj
+++ b/src/Taxjar/Taxjar.csproj
@@ -29,6 +29,7 @@
   <ItemGroup>
     <PackageReference Include="Newtonsoft.Json" Version="12.0.3" />
     <PackageReference Include="RestSharp" Version="106.10.1" />
+    <PackageReference Include="RestSharp.Serializers.NewtonsoftJson" Version="106.10.1" />
   </ItemGroup>
 
 </Project>
diff --git a/src/Taxjar/TaxjarApi.cs b/src/Taxjar/TaxjarApi.cs
index 7cff543..8931e68 100644
--- a/src/Taxjar/TaxjarApi.cs
+++ b/src/Taxjar/TaxjarApi.cs
@@ -8,6 +8,7 @@
 using Newtonsoft.Json;
 using Newtonsoft.Json.Linq;
 using RestSharp;
+using RestSharp.Serializers.NewtonsoftJson;
 using Taxjar.Infrastructure;
 using RestRequest = RestSharp.RestRequest;
 
@@ -83,7 +84,7 @@ protected virtual RestRequest CreateRequest(string action, Method method = Metho
         {
             var request = new RestRequest(action, method)
             {
-                RequestFormat = DataFormat.Json
+                RequestFormat = DataFormat.Json, JsonSerializer = new JsonNetSerializer()
             };
             var includeBody = new[] {Method.POST, Method.PUT, Method.PATCH}.Contains(method);