diff --git a/src/Mollie.Api/Client/Abstract/IBalanceClient.cs b/src/Mollie.Api/Client/Abstract/IBalanceClient.cs
index 952c3149..ecfa31b4 100644
--- a/src/Mollie.Api/Client/Abstract/IBalanceClient.cs
+++ b/src/Mollie.Api/Client/Abstract/IBalanceClient.cs
@@ -7,7 +7,7 @@
 using Mollie.Api.Models.Url;
 
 namespace Mollie.Api.Client.Abstract {
-    public interface IBalanceClient : IDisposable {
+    public interface IBalanceClient : IBaseMollieClient {
         Task<BalanceResponse> GetBalanceAsync(string balanceId);
         Task<BalanceResponse> GetBalanceAsync(UrlObjectLink<BalanceResponse> url);
         Task<BalanceResponse> GetPrimaryBalanceAsync();
diff --git a/src/Mollie.Api/Client/Abstract/IBaseMollieClient.cs b/src/Mollie.Api/Client/Abstract/IBaseMollieClient.cs
new file mode 100644
index 00000000..f64da5fe
--- /dev/null
+++ b/src/Mollie.Api/Client/Abstract/IBaseMollieClient.cs
@@ -0,0 +1,9 @@
+using System;
+
+namespace Mollie.Api.Client.Abstract
+{
+    public interface IBaseMollieClient : IDisposable
+    {
+        IDisposable WithIdempotencyKey(string value);
+    }
+}
\ No newline at end of file
diff --git a/src/Mollie.Api/Client/Abstract/ICaptureClient.cs b/src/Mollie.Api/Client/Abstract/ICaptureClient.cs
index 0fd49447..ce8d8db3 100644
--- a/src/Mollie.Api/Client/Abstract/ICaptureClient.cs
+++ b/src/Mollie.Api/Client/Abstract/ICaptureClient.cs
@@ -1,12 +1,11 @@
-using System;
-using System.Threading.Tasks;
+using System.Threading.Tasks;
 using Mollie.Api.Models.List;
 using Mollie.Api.Models.Capture;
 using Mollie.Api.Models.Capture.Request;
 using Mollie.Api.Models.Url;
 
 namespace Mollie.Api.Client.Abstract {
-    public interface ICaptureClient : IDisposable {
+    public interface ICaptureClient : IBaseMollieClient {
         Task<CaptureResponse> GetCaptureAsync(string paymentId, string captureId, bool testmode = false);
         Task<CaptureResponse> GetCaptureAsync(UrlObjectLink<CaptureResponse> url);
         Task<ListResponse<CaptureResponse>> GetCapturesListAsync(string paymentId, bool testmode = false);
diff --git a/src/Mollie.Api/Client/Abstract/IChargebacksClient.cs b/src/Mollie.Api/Client/Abstract/IChargebacksClient.cs
index 9e676b1c..0db8ad3e 100644
--- a/src/Mollie.Api/Client/Abstract/IChargebacksClient.cs
+++ b/src/Mollie.Api/Client/Abstract/IChargebacksClient.cs
@@ -1,11 +1,10 @@
-using System;
-using System.Threading.Tasks;
+using System.Threading.Tasks;
 using Mollie.Api.Models.Chargeback;
 using Mollie.Api.Models.List;
 using Mollie.Api.Models.Url;
 
 namespace Mollie.Api.Client.Abstract {
-    public interface IChargebacksClient : IDisposable {
+    public interface IChargebacksClient : IBaseMollieClient {
         Task<ChargebackResponse> GetChargebackAsync(string paymentId, string chargebackId, bool testmode = false);
         Task<ListResponse<ChargebackResponse>> GetChargebacksListAsync(string paymentId, string from = null, int? limit = null, bool testmode = false);
         Task<ListResponse<ChargebackResponse>> GetChargebacksListAsync(string profileId = null, bool testmode = false);
diff --git a/src/Mollie.Api/Client/Abstract/ICustomerClient.cs b/src/Mollie.Api/Client/Abstract/ICustomerClient.cs
index 70e848ff..4bbddffa 100644
--- a/src/Mollie.Api/Client/Abstract/ICustomerClient.cs
+++ b/src/Mollie.Api/Client/Abstract/ICustomerClient.cs
@@ -1,5 +1,4 @@
-using System;
-using System.Threading.Tasks;
+using System.Threading.Tasks;
 using Mollie.Api.Models.Customer;
 using Mollie.Api.Models.List;
 using Mollie.Api.Models.Payment.Request;
@@ -7,7 +6,7 @@
 using Mollie.Api.Models.Url;
 
 namespace Mollie.Api.Client.Abstract {
-    public interface ICustomerClient : IDisposable {
+    public interface ICustomerClient : IBaseMollieClient {
         Task<CustomerResponse> CreateCustomerAsync(CustomerRequest request);
         Task<CustomerResponse> UpdateCustomerAsync(string customerId, CustomerRequest request);
         Task DeleteCustomerAsync(string customerId, bool testmode = false);
diff --git a/src/Mollie.Api/Client/Abstract/IInvoicesClient.cs b/src/Mollie.Api/Client/Abstract/IInvoicesClient.cs
index b99d9981..ca69b014 100644
--- a/src/Mollie.Api/Client/Abstract/IInvoicesClient.cs
+++ b/src/Mollie.Api/Client/Abstract/IInvoicesClient.cs
@@ -1,12 +1,11 @@
-using System;
-using System.Threading.Tasks;
+using System.Threading.Tasks;
 using Mollie.Api.Models.Invoice;
 using Mollie.Api.Models.List;
 
 using Mollie.Api.Models.Url;
 
 namespace Mollie.Api.Client.Abstract {
-    public interface IInvoicesClient : IDisposable {
+    public interface IInvoicesClient : IBaseMollieClient {
         Task<InvoiceResponse> GetInvoiceAsync(string invoiceId);
         Task<InvoiceResponse> GetInvoiceAsync(UrlObjectLink<InvoiceResponse> url);
         Task<ListResponse<InvoiceResponse>> GetInvoiceListAsync(
diff --git a/src/Mollie.Api/Client/Abstract/IMandateClient.cs b/src/Mollie.Api/Client/Abstract/IMandateClient.cs
index 9ea03015..7dcebee6 100644
--- a/src/Mollie.Api/Client/Abstract/IMandateClient.cs
+++ b/src/Mollie.Api/Client/Abstract/IMandateClient.cs
@@ -1,11 +1,10 @@
-using System;
-using System.Threading.Tasks;
+using System.Threading.Tasks;
 using Mollie.Api.Models.List;
 using Mollie.Api.Models.Mandate;
 using Mollie.Api.Models.Url;
 
 namespace Mollie.Api.Client.Abstract {
-    public interface IMandateClient : IDisposable {
+    public interface IMandateClient : IBaseMollieClient {
         Task<MandateResponse> GetMandateAsync(string customerId, string mandateId, bool testmode = false);
         Task<ListResponse<MandateResponse>> GetMandateListAsync(string customerId, string from = null, int? limit = null, bool testmode = false);
         Task<MandateResponse> CreateMandateAsync(string customerId, MandateRequest request);
diff --git a/src/Mollie.Api/Client/Abstract/IOnboardingClient.cs b/src/Mollie.Api/Client/Abstract/IOnboardingClient.cs
index 8ded51f4..3d626e66 100644
--- a/src/Mollie.Api/Client/Abstract/IOnboardingClient.cs
+++ b/src/Mollie.Api/Client/Abstract/IOnboardingClient.cs
@@ -1,10 +1,9 @@
-using System;
-using Mollie.Api.Models.Onboarding.Request;
+using Mollie.Api.Models.Onboarding.Request;
 using Mollie.Api.Models.Onboarding.Response;
 using System.Threading.Tasks;
 
 namespace Mollie.Api.Client.Abstract {
-    public interface IOnboardingClient : IDisposable {
+    public interface IOnboardingClient : IBaseMollieClient {
         /// <summary>
         /// Get the status of onboarding of the authenticated organization.
         /// </summary>
diff --git a/src/Mollie.Api/Client/Abstract/IOrderClient.cs b/src/Mollie.Api/Client/Abstract/IOrderClient.cs
index 87a713e5..c411fb2c 100644
--- a/src/Mollie.Api/Client/Abstract/IOrderClient.cs
+++ b/src/Mollie.Api/Client/Abstract/IOrderClient.cs
@@ -1,5 +1,4 @@
-using System;
-using System.Threading.Tasks;
+using System.Threading.Tasks;
 using Mollie.Api.Models;
 using Mollie.Api.Models.List;
 using Mollie.Api.Models.Order;
@@ -9,7 +8,7 @@
 using Mollie.Api.Models.Url;
 
 namespace Mollie.Api.Client.Abstract {
-    public interface IOrderClient : IDisposable {
+    public interface IOrderClient : IBaseMollieClient {
         Task<OrderResponse> CreateOrderAsync(OrderRequest orderRequest);
         Task<OrderResponse> GetOrderAsync(
             string orderId, bool embedPayments = false, bool embedRefunds = false, bool embedShipments = false, bool testmode = false);
diff --git a/src/Mollie.Api/Client/Abstract/IOrganizationsClient.cs b/src/Mollie.Api/Client/Abstract/IOrganizationsClient.cs
index feaefe41..18e9ab9a 100644
--- a/src/Mollie.Api/Client/Abstract/IOrganizationsClient.cs
+++ b/src/Mollie.Api/Client/Abstract/IOrganizationsClient.cs
@@ -1,11 +1,10 @@
-using System;
-using System.Threading.Tasks;
+using System.Threading.Tasks;
 using Mollie.Api.Models.List;
 using Mollie.Api.Models.Organization;
 using Mollie.Api.Models.Url;
 
 namespace Mollie.Api.Client.Abstract {
-    public interface IOrganizationsClient : IDisposable {
+    public interface IOrganizationsClient : IBaseMollieClient {
         Task<OrganizationResponse> GetCurrentOrganizationAsync();
         Task<OrganizationResponse> GetOrganizationAsync(string organizationId);
         Task<ListResponse<OrganizationResponse>> GetOrganizationsListAsync(string from = null, int? limit = null);
diff --git a/src/Mollie.Api/Client/Abstract/IPaymentClient.cs b/src/Mollie.Api/Client/Abstract/IPaymentClient.cs
index c2ef6a0c..4378b365 100644
--- a/src/Mollie.Api/Client/Abstract/IPaymentClient.cs
+++ b/src/Mollie.Api/Client/Abstract/IPaymentClient.cs
@@ -1,5 +1,4 @@
-using System;
-using System.Threading.Tasks;
+using System.Threading.Tasks;
 using Mollie.Api.Models;
 using Mollie.Api.Models.List;
 using Mollie.Api.Models.Payment.Request;
@@ -7,7 +6,7 @@
 using Mollie.Api.Models.Url;
 
 namespace Mollie.Api.Client.Abstract {
-    public interface IPaymentClient : IDisposable {
+    public interface IPaymentClient : IBaseMollieClient {
         Task<PaymentResponse> CreatePaymentAsync(PaymentRequest paymentRequest, bool includeQrCode = false);
 
         /// <summary>
diff --git a/src/Mollie.Api/Client/Abstract/IPaymentLinkClient.cs b/src/Mollie.Api/Client/Abstract/IPaymentLinkClient.cs
index a30cf887..c6359c22 100644
--- a/src/Mollie.Api/Client/Abstract/IPaymentLinkClient.cs
+++ b/src/Mollie.Api/Client/Abstract/IPaymentLinkClient.cs
@@ -1,12 +1,11 @@
-using System;
-using System.Threading.Tasks;
+using System.Threading.Tasks;
 using Mollie.Api.Models.List;
 using Mollie.Api.Models.PaymentLink.Request;
 using Mollie.Api.Models.PaymentLink.Response;
 using Mollie.Api.Models.Url;
 
 namespace Mollie.Api.Client.Abstract {
-    public interface IPaymentLinkClient : IDisposable {
+    public interface IPaymentLinkClient : IBaseMollieClient {
         Task<PaymentLinkResponse> CreatePaymentLinkAsync(PaymentLinkRequest paymentLinkRequest);
 
         /// <summary>
diff --git a/src/Mollie.Api/Client/Abstract/IPaymentMethodClient.cs b/src/Mollie.Api/Client/Abstract/IPaymentMethodClient.cs
index fe2dbfc7..79f7e4a0 100644
--- a/src/Mollie.Api/Client/Abstract/IPaymentMethodClient.cs
+++ b/src/Mollie.Api/Client/Abstract/IPaymentMethodClient.cs
@@ -1,5 +1,4 @@
-using System;
-using System.Threading.Tasks;
+using System.Threading.Tasks;
 using Mollie.Api.Models;
 using Mollie.Api.Models.List;
 using Mollie.Api.Models.Payment;
@@ -7,7 +6,7 @@
 using Mollie.Api.Models.Url;
 
 namespace Mollie.Api.Client.Abstract {
-    public interface IPaymentMethodClient : IDisposable {
+    public interface IPaymentMethodClient : IBaseMollieClient {
 		Task<PaymentMethodResponse> GetPaymentMethodAsync(
             string paymentMethod, 
             bool includeIssuers = false, 
diff --git a/src/Mollie.Api/Client/Abstract/IPermissionsClient.cs b/src/Mollie.Api/Client/Abstract/IPermissionsClient.cs
index 9e1f3e05..8d4f9fb9 100644
--- a/src/Mollie.Api/Client/Abstract/IPermissionsClient.cs
+++ b/src/Mollie.Api/Client/Abstract/IPermissionsClient.cs
@@ -1,11 +1,10 @@
-using System;
-using System.Threading.Tasks;
+using System.Threading.Tasks;
 using Mollie.Api.Models.List;
 using Mollie.Api.Models.Permission;
 using Mollie.Api.Models.Url;
 
 namespace Mollie.Api.Client.Abstract {
-    public interface IPermissionsClient : IDisposable {
+    public interface IPermissionsClient : IBaseMollieClient {
         Task<PermissionResponse> GetPermissionAsync(string permissionId);
         Task<PermissionResponse> GetPermissionAsync(UrlObjectLink<PermissionResponse> url);
         Task<ListResponse<PermissionResponse>> GetPermissionListAsync();
diff --git a/src/Mollie.Api/Client/Abstract/IProfileClient.cs b/src/Mollie.Api/Client/Abstract/IProfileClient.cs
index 0f2d5bfe..e083eacc 100644
--- a/src/Mollie.Api/Client/Abstract/IProfileClient.cs
+++ b/src/Mollie.Api/Client/Abstract/IProfileClient.cs
@@ -1,5 +1,4 @@
-using System;
-using System.Threading.Tasks;
+using System.Threading.Tasks;
 using Mollie.Api.Models.List;
 using Mollie.Api.Models.PaymentMethod;
 using Mollie.Api.Models.Profile.Request;
@@ -7,7 +6,7 @@
 using Mollie.Api.Models.Url;
 
 namespace Mollie.Api.Client.Abstract {
-    public interface IProfileClient : IDisposable {
+    public interface IProfileClient : IBaseMollieClient {
         Task<ProfileResponse> CreateProfileAsync(ProfileRequest request);
         Task<ProfileResponse> GetProfileAsync(string profileId);
         Task<ProfileResponse> GetProfileAsync(UrlObjectLink<ProfileResponse> url);
diff --git a/src/Mollie.Api/Client/Abstract/IRefundClient.cs b/src/Mollie.Api/Client/Abstract/IRefundClient.cs
index b47fb415..3223da69 100644
--- a/src/Mollie.Api/Client/Abstract/IRefundClient.cs
+++ b/src/Mollie.Api/Client/Abstract/IRefundClient.cs
@@ -1,11 +1,10 @@
-using System;
-using System.Threading.Tasks;
+using System.Threading.Tasks;
 using Mollie.Api.Models.List;
 using Mollie.Api.Models.Refund;
 using Mollie.Api.Models.Url;
 
 namespace Mollie.Api.Client.Abstract {
-    public interface IRefundClient : IDisposable {
+    public interface IRefundClient : IBaseMollieClient {
         Task CancelRefundAsync(string paymentId, string refundId, bool testmode = false);
         Task<RefundResponse> CreateRefundAsync(string paymentId, RefundRequest refundRequest);
         Task<RefundResponse> GetRefundAsync(string paymentId, string refundId, bool testmode = false);
diff --git a/src/Mollie.Api/Client/Abstract/ISettlementsClient.cs b/src/Mollie.Api/Client/Abstract/ISettlementsClient.cs
index dec04c2c..e272fbb3 100644
--- a/src/Mollie.Api/Client/Abstract/ISettlementsClient.cs
+++ b/src/Mollie.Api/Client/Abstract/ISettlementsClient.cs
@@ -9,7 +9,7 @@
 using Mollie.Api.Models.Url;
 
 namespace Mollie.Api.Client.Abstract {
-    public interface ISettlementsClient : IDisposable {
+    public interface ISettlementsClient : IBaseMollieClient {
         Task<SettlementResponse> GetSettlementAsync(string settlementId);
         Task<SettlementResponse> GetNextSettlement();
         Task<SettlementResponse> GetOpenSettlement();
diff --git a/src/Mollie.Api/Client/Abstract/IShipmentClient.cs b/src/Mollie.Api/Client/Abstract/IShipmentClient.cs
index 5c22ecef..36acccac 100644
--- a/src/Mollie.Api/Client/Abstract/IShipmentClient.cs
+++ b/src/Mollie.Api/Client/Abstract/IShipmentClient.cs
@@ -1,11 +1,10 @@
-using System;
-using System.Threading.Tasks;
+using System.Threading.Tasks;
 using Mollie.Api.Models.List;
 using Mollie.Api.Models.Shipment;
 using Mollie.Api.Models.Url;
 
 namespace Mollie.Api.Client.Abstract {
-    public interface IShipmentClient : IDisposable {
+    public interface IShipmentClient : IBaseMollieClient {
         Task<ShipmentResponse> CreateShipmentAsync(string orderId, ShipmentRequest shipmentRequest);
         Task<ShipmentResponse> GetShipmentAsync(string orderId, string shipmentId, bool testmode = false);
         Task<ShipmentResponse> GetShipmentAsync(UrlObjectLink<ShipmentResponse> url);
diff --git a/src/Mollie.Api/Client/Abstract/ISubscriptionClient.cs b/src/Mollie.Api/Client/Abstract/ISubscriptionClient.cs
index 95945d45..6b37f40a 100644
--- a/src/Mollie.Api/Client/Abstract/ISubscriptionClient.cs
+++ b/src/Mollie.Api/Client/Abstract/ISubscriptionClient.cs
@@ -1,12 +1,11 @@
-using System;
-using System.Threading.Tasks;
+using System.Threading.Tasks;
 using Mollie.Api.Models.List;
 using Mollie.Api.Models.Payment.Response;
 using Mollie.Api.Models.Subscription;
 using Mollie.Api.Models.Url;
 
 namespace Mollie.Api.Client.Abstract {
-    public interface ISubscriptionClient : IDisposable {
+    public interface ISubscriptionClient : IBaseMollieClient {
         Task CancelSubscriptionAsync(string customerId, string subscriptionId, bool testmode = false);
         Task<SubscriptionResponse> CreateSubscriptionAsync(string customerId, SubscriptionRequest request);
         Task<SubscriptionResponse> GetSubscriptionAsync(string customerId, string subscriptionId, bool testmode = false);
diff --git a/src/Mollie.Api/Client/Abstract/ITerminalClient.cs b/src/Mollie.Api/Client/Abstract/ITerminalClient.cs
index 625979f7..21548137 100644
--- a/src/Mollie.Api/Client/Abstract/ITerminalClient.cs
+++ b/src/Mollie.Api/Client/Abstract/ITerminalClient.cs
@@ -1,5 +1,4 @@
-using System;
-using System.Threading.Tasks;
+using System.Threading.Tasks;
 using Mollie.Api.Models.List;
 using Mollie.Api.Models.Terminal;
 using Mollie.Api.Models.Url;
@@ -8,7 +7,7 @@ namespace Mollie.Api.Client.Abstract
 {    /// <summary>
      /// Calls in this class are documented in https://docs.mollie.com/reference/v2/terminals-api/overview
      /// </summary>
-    public interface ITerminalClient : IDisposable {
+    public interface ITerminalClient : IBaseMollieClient {
         Task<TerminalResponse> GetTerminalAsync(string terminalId);
         Task<TerminalResponse> GetTerminalAsync(UrlObjectLink<TerminalResponse> url);
         Task<ListResponse<TerminalResponse>> GetTerminalListAsync(string from = null, int? limit = null, string profileId = null, bool testmode = false);
diff --git a/src/Mollie.Api/Client/Abstract/IWalletClient.cs b/src/Mollie.Api/Client/Abstract/IWalletClient.cs
index 27d31216..313f4310 100644
--- a/src/Mollie.Api/Client/Abstract/IWalletClient.cs
+++ b/src/Mollie.Api/Client/Abstract/IWalletClient.cs
@@ -3,7 +3,7 @@
 using Mollie.Api.Models.Wallet.Response;
 
 namespace Mollie.Api.Client.Abstract {
-    public interface IWalletClient {
+    public interface IWalletClient : IBaseMollieClient {
         Task<ApplePayPaymentSessionResponse> RequestApplePayPaymentSessionAsync(ApplePayPaymentSessionRequest request);
     }
 }
\ No newline at end of file
diff --git a/src/Mollie.Api/Client/BaseMollieClient.cs b/src/Mollie.Api/Client/BaseMollieClient.cs
index 67dfe22c..def79834 100644
--- a/src/Mollie.Api/Client/BaseMollieClient.cs
+++ b/src/Mollie.Api/Client/BaseMollieClient.cs
@@ -8,6 +8,7 @@
 using System.Threading.Tasks;
 using Mollie.Api.Extensions;
 using Mollie.Api.Framework;
+using Mollie.Api.Framework.Idempotency;
 using Mollie.Api.Models.Url;
 
 namespace Mollie.Api.Client {
@@ -17,6 +18,8 @@ public abstract class BaseMollieClient : IDisposable {
         private readonly string _apiKey;
         private readonly HttpClient _httpClient;
         private readonly JsonConverterService _jsonConverterService;
+        
+        private readonly AsyncLocalVariable<string> _idempotencyKey = new AsyncLocalVariable<string>(null);
 
         private readonly bool _createdHttpClient = false;
 
@@ -37,6 +40,11 @@ protected BaseMollieClient(HttpClient httpClient = null, string apiEndpoint = Ap
             this._createdHttpClient = httpClient == null;
             this._httpClient = httpClient ?? new HttpClient();
         }
+        
+        public IDisposable WithIdempotencyKey(string value) {
+            _idempotencyKey.Value = value;
+            return _idempotencyKey;
+        }
 
         private async Task<T> SendHttpRequest<T>(HttpMethod httpMethod, string relativeUri, object data = null) {
             HttpRequestMessage httpRequest = this.CreateHttpRequest(httpMethod, relativeUri);
@@ -127,7 +135,8 @@ protected virtual HttpRequestMessage CreateHttpRequest(HttpMethod method, string
             httpRequest.Headers.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
             httpRequest.Headers.Authorization = new AuthenticationHeaderValue("Bearer", this._apiKey);
             httpRequest.Headers.Add("User-Agent", this.GetUserAgent());
-            httpRequest.Headers.Add("Idempotency-Key", Guid.NewGuid().ToString());
+            var idemPotencyKey = _idempotencyKey.Value ?? Guid.NewGuid().ToString();
+            httpRequest.Headers.Add("Idempotency-Key", idemPotencyKey);
             httpRequest.Content = content;
 
             return httpRequest;
diff --git a/src/Mollie.Api/Framework/Idempotency/AsyncLocalVariable.cs b/src/Mollie.Api/Framework/Idempotency/AsyncLocalVariable.cs
new file mode 100644
index 00000000..329f3aed
--- /dev/null
+++ b/src/Mollie.Api/Framework/Idempotency/AsyncLocalVariable.cs
@@ -0,0 +1,26 @@
+using System;
+using System.Threading;
+
+namespace Mollie.Api.Framework.Idempotency
+{
+    public class AsyncLocalVariable<T> : IDisposable where T : class
+    {
+        private readonly AsyncLocal<T> _asyncLocal = new AsyncLocal<T>();
+
+        public T Value
+        {
+            get => _asyncLocal.Value;
+            set => _asyncLocal.Value = value;
+        }
+
+        public AsyncLocalVariable(T value)
+        {
+            _asyncLocal.Value = value;
+        }
+
+        public void Dispose()
+        {
+            _asyncLocal.Value = null;
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/Mollie.Api/Mollie.Api.csproj b/src/Mollie.Api/Mollie.Api.csproj
index 9bf51458..0e3d4f35 100644
--- a/src/Mollie.Api/Mollie.Api.csproj
+++ b/src/Mollie.Api/Mollie.Api.csproj
@@ -18,8 +18,7 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.Extensions.DependencyInjection.Abstractions" Version="7.0.0" />
-    <PackageReference Include="Microsoft.Extensions.Http.Polly" Version="7.0.10" />
+    <PackageReference Include="Microsoft.Extensions.Http.Polly" Version="6.0.28" />
     <PackageReference Include="Newtonsoft.Json" Version="13.0.3" />
     <PackageReference Include="System.Runtime.Serialization.Primitives" Version="4.3.0" />    
   </ItemGroup>
diff --git a/tests/Mollie.Tests.Integration/Api/PaymentTests.cs b/tests/Mollie.Tests.Integration/Api/PaymentTests.cs
index 6ce27b2e..cfd1d42e 100644
--- a/tests/Mollie.Tests.Integration/Api/PaymentTests.cs
+++ b/tests/Mollie.Tests.Integration/Api/PaymentTests.cs
@@ -102,6 +102,26 @@ public async Task CanCreateDefaultPaymentWithOnlyRequiredFields() {
         result.Description.Should().Be(paymentRequest.Description);
         result.RedirectUrl.Should().Be(paymentRequest.RedirectUrl);
     }
+    
+    [DefaultRetryFact]
+    public async Task CanCreateDefaultPaymentWithCustomIdempotencyKey() {
+        // Given: we create a payment request with only the required parameters
+        PaymentRequest paymentRequest = new PaymentRequest() {
+            Amount = new Amount(Currency.EUR, "100.00"),
+            Description = "Description",
+            RedirectUrl = DefaultRedirectUrl
+        };
+
+        // When: We send the payment request to Mollie
+        using (_paymentClient.WithIdempotencyKey("my-idempotency-key"))
+        {
+            PaymentResponse firstAttempt = await _paymentClient.CreatePaymentAsync(paymentRequest);
+            PaymentResponse secondAttempt = await _paymentClient.CreatePaymentAsync(paymentRequest);
+            
+            // Then: Make sure the responses have the same payment Id
+            firstAttempt.Id.Should().Be(secondAttempt.Id);
+        }
+    }
 
     [DefaultRetryFact]
     public async Task CanCreateDefaultPaymentWithAllFields() {
diff --git a/tests/Mollie.Tests.Unit/Client/PaymentClientTests.cs b/tests/Mollie.Tests.Unit/Client/PaymentClientTests.cs
index 2ea5c082..297f227d 100644
--- a/tests/Mollie.Tests.Unit/Client/PaymentClientTests.cs
+++ b/tests/Mollie.Tests.Unit/Client/PaymentClientTests.cs
@@ -6,6 +6,7 @@
 using Mollie.Api.Models.Payment.Response;
 using RichardSzalay.MockHttp;
 using System.Collections.Generic;
+using System.Linq;
 using System.Net.Http;
 using System.Threading.Tasks;
 using FluentAssertions;
@@ -16,6 +17,43 @@
 namespace Mollie.Tests.Unit.Client;
 
 public class PaymentClientTests : BaseClientTests {
+    [Fact]
+    public async Task CreatePaymentAsync_WithCustomIdempotencyKey_CustomIdemPotencyKeyIsSent()
+    {
+        // Given: We create a payment request with only the required parameters
+        PaymentRequest paymentRequest = new PaymentRequest()
+        {
+            Amount = new Amount(Currency.EUR, "100.00"),
+            Description = "Description",
+            RedirectUrl = "http://www.mollie.com"
+        };
+        const string customIdempotencyKey1 = "my-idempotency-key-1";
+        const string customIdempotencyKey2 = "my-idempotency-key-2";
+        const string jsonToReturnInMockResponse = defaultPaymentJsonResponse;
+        var mockHttp = new MockHttpMessageHandler();
+        mockHttp.Expect(HttpMethod.Post, $"{BaseMollieClient.ApiEndPoint}*")
+            .WithHeaders("Idempotency-Key", customIdempotencyKey1)
+            .Respond("application/json", jsonToReturnInMockResponse);
+        mockHttp.Expect(HttpMethod.Post, $"{BaseMollieClient.ApiEndPoint}*")
+            .WithHeaders("Idempotency-Key", customIdempotencyKey2)
+            .Respond("application/json", jsonToReturnInMockResponse);
+        HttpClient httpClient = mockHttp.ToHttpClient();
+        PaymentClient paymentClient = new PaymentClient("abcde", httpClient);
+
+        // Act
+        using (paymentClient.WithIdempotencyKey(customIdempotencyKey1))
+        {
+            await paymentClient.CreatePaymentAsync(paymentRequest);
+        }
+        using (paymentClient.WithIdempotencyKey(customIdempotencyKey2))
+        {
+            await paymentClient.CreatePaymentAsync(paymentRequest);
+        }
+
+        // Assert
+        mockHttp.VerifyNoOutstandingExpectation();
+    }
+    
     [Fact]
     public async Task CreatePaymentAsync_PaymentWithRequiredParameters_ResponseIsDeserializedInExpectedFormat() {
         // Given: we create a payment request with only the required parameters
diff --git a/tests/Mollie.Tests.Unit/DependencyInjectionTests.cs b/tests/Mollie.Tests.Unit/DependencyInjectionTests.cs
index 5d29fba2..01b3b177 100644
--- a/tests/Mollie.Tests.Unit/DependencyInjectionTests.cs
+++ b/tests/Mollie.Tests.Unit/DependencyInjectionTests.cs
@@ -34,8 +34,11 @@ public void AddMollieClient_ShouldRegisterAllApiInterfaces()
             .Where(type => type.Namespace == typeof(IPaymentClient).Namespace);
         foreach (var apiClientInterface in apiClientInterfaces)
         {
-            var apiClientImplementation = serviceProvider.GetService(apiClientInterface);
-            apiClientImplementation.Should().NotBeNull();
+            if (apiClientInterface != typeof(IBaseMollieClient))
+            {
+                var apiClientImplementation = serviceProvider.GetService(apiClientInterface);
+                apiClientImplementation.Should().NotBeNull();
+            }
         }
     }
 }
\ No newline at end of file