diff --git a/packages/http-client-csharp/generator/Microsoft.Generator.CSharp.ClientModel/test/Providers/ClientProviders/ClientProviderCustomizationTests.cs b/packages/http-client-csharp/generator/Microsoft.Generator.CSharp.ClientModel/test/Providers/ClientProviders/ClientProviderCustomizationTests.cs
new file mode 100644
index 0000000000..b4fae5cbc3
--- /dev/null
+++ b/packages/http-client-csharp/generator/Microsoft.Generator.CSharp.ClientModel/test/Providers/ClientProviders/ClientProviderCustomizationTests.cs
@@ -0,0 +1,118 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+using System;
+using System.ClientModel;
+using System.Linq;
+using System.Threading.Tasks;
+using Microsoft.Generator.CSharp.ClientModel.Providers;
+using Microsoft.Generator.CSharp.Input;
+using Microsoft.Generator.CSharp.Tests.Common;
+using NUnit.Framework;
+
+namespace Microsoft.Generator.CSharp.ClientModel.Tests.Providers.ClientProviders
+{
+    public class ClientProviderCustomizationTests
+    {
+        [Test]
+        public async Task CanAddMethod()
+        {
+            var inputOperation = InputFactory.Operation("HelloAgain", parameters:
+            [
+                InputFactory.Parameter("p1", InputFactory.Array(InputPrimitiveType.String))
+            ]);
+            var inputClient = InputFactory.Client("TestClient", operations: [inputOperation]);
+            var plugin = await MockHelpers.LoadMockPluginAsync(
+                clients: () => [inputClient],
+                compilation: async () => await Helpers.GetCompilationFromDirectoryAsync());
+
+            // Find the client provider
+            var clientProvider = plugin.Object.OutputLibrary.TypeProviders.SingleOrDefault(t => t is ClientProvider);
+            Assert.IsNotNull(clientProvider);
+
+            var clientProviderMethods = clientProvider!.Methods;
+            Assert.AreEqual(4, clientProviderMethods.Count);
+            Assert.IsFalse(clientProviderMethods.Any(m => m.Signature.Name == "NewMethod"));
+
+            // The custom code view should contain the method
+            var customCodeView = clientProvider.CustomCodeView;
+            Assert.IsNotNull(customCodeView);
+            var customMethods = customCodeView!.Methods;
+            Assert.AreEqual(1, customMethods.Count);
+            Assert.AreEqual("NewMethod", customMethods[0].Signature.Name);
+            Assert.AreEqual(customMethods[0].Signature.Parameters.Count, 2);
+            Assert.IsNull(customMethods[0].BodyExpression);
+            Assert.AreEqual(string.Empty, customMethods[0].BodyStatements!.ToDisplayString());
+        }
+
+        [Test]
+        public async Task CanAddMultipleMethods()
+        {
+            var inputOperation = InputFactory.Operation("HelloAgain", parameters:
+            [
+                InputFactory.Parameter("p1", InputFactory.Array(InputPrimitiveType.String))
+            ]);
+            var inputClient = InputFactory.Client("TestClient", operations: [inputOperation]);
+            var plugin = await MockHelpers.LoadMockPluginAsync(
+                clients: () => [inputClient],
+                compilation: async () => await Helpers.GetCompilationFromDirectoryAsync());
+
+            // Find the client provider
+            var clientProvider = plugin.Object.OutputLibrary.TypeProviders.SingleOrDefault(t => t is ClientProvider);
+            Assert.IsNotNull(clientProvider);
+
+            var clientProviderMethods = clientProvider!.Methods;
+            Assert.AreEqual(4, clientProviderMethods.Count);
+
+            // The custom code view should contain the method
+            var customCodeView = clientProvider.CustomCodeView;
+            Assert.IsNotNull(customCodeView);
+            var customMethods = customCodeView!.Methods;
+            Assert.AreEqual(4, customMethods.Count);
+            Assert.AreEqual("NewMethodOne", customMethods[0].Signature.Name);
+            Assert.AreEqual(customMethods[0].Signature.Parameters.Count, 2);
+            Assert.AreEqual("NewMethodTwo", customMethods[1].Signature.Name);
+            Assert.AreEqual(customMethods[1].Signature.Parameters.Count, 0);
+            Assert.AreEqual("NewMethodThree", customMethods[2].Signature.Name);
+            Assert.AreEqual(customMethods[2].Signature.Parameters.Count, 1);
+            Assert.AreEqual("NewMethodFour", customMethods[3].Signature.Name);
+            Assert.AreEqual(customMethods[3].Signature.Parameters.Count, 1);
+        }
+
+        // Validates that the custom method is added when the method has the same name as an existing method but different parameters
+        [Test]
+        public async Task CanAddMethodSameName()
+        {
+            var inputOperation = InputFactory.Operation("HelloAgain", parameters:
+            [
+                InputFactory.Parameter("p1", InputFactory.Array(InputPrimitiveType.String))
+            ]);
+            var inputClient = InputFactory.Client("TestClient", operations: [inputOperation]);
+            var plugin = await MockHelpers.LoadMockPluginAsync(
+                clients: () => [inputClient],
+                compilation: async () => await Helpers.GetCompilationFromDirectoryAsync());
+
+            // Find the client provider
+            var clientProvider = plugin.Object.OutputLibrary.TypeProviders.SingleOrDefault(t => t is ClientProvider);
+            Assert.IsNotNull(clientProvider);
+
+            var clientProviderMethods = clientProvider!.Methods;
+            Assert.AreEqual(4, clientProviderMethods.Count);
+
+            var helloAgainMethod = clientProviderMethods.FirstOrDefault(m
+                => m.Signature.Name == "HelloAgain" && m.Signature.Parameters.Count > 0 && m.Signature.Parameters[0].Name == "p1");
+            Assert.IsNotNull(helloAgainMethod);
+            Assert.AreEqual(1, helloAgainMethod!.Signature.Parameters.Count);
+
+            // The custom code view should contain the method
+            var customCodeView = clientProvider.CustomCodeView;
+            Assert.IsNotNull(customCodeView);
+            var customMethods = customCodeView!.Methods;
+            Assert.AreEqual(1, customMethods.Count);
+            Assert.AreEqual("HelloAgain", customMethods[0].Signature.Name);
+            Assert.AreEqual(customMethods[0].Signature.Parameters.Count, 2);
+            Assert.IsNull(customMethods[0].BodyExpression);
+            Assert.AreEqual(string.Empty, customMethods[0].BodyStatements!.ToDisplayString());
+        }
+    }
+}
diff --git a/packages/http-client-csharp/generator/Microsoft.Generator.CSharp.ClientModel/test/Providers/ClientProviders/TestData/ClientProviderCustomizationTests/CanAddMethod/CanAddMethod.cs b/packages/http-client-csharp/generator/Microsoft.Generator.CSharp.ClientModel/test/Providers/ClientProviders/TestData/ClientProviderCustomizationTests/CanAddMethod/CanAddMethod.cs
new file mode 100644
index 0000000000..4bb20ab75f
--- /dev/null
+++ b/packages/http-client-csharp/generator/Microsoft.Generator.CSharp.ClientModel/test/Providers/ClientProviders/TestData/ClientProviderCustomizationTests/CanAddMethod/CanAddMethod.cs
@@ -0,0 +1,25 @@
+// <auto-generated/>
+
+#nullable disable
+
+using System;
+using System.ClientModel;
+using System.ClientModel.Primitives;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+
+namespace Sample
+{
+    /// <summary></summary>
+    public partial class TestClient
+    {
+        public virtual ClientResult NewMethod(BinaryContent content, RequestOptions options)
+        {
+            Argument.AssertNotNull(content, nameof(content));
+
+            using PipelineMessage message = CreateRequest(content, options);
+            return ClientResult.FromResponse(Pipeline.ProcessMessage(message, options));
+        }
+    }
+}
diff --git a/packages/http-client-csharp/generator/Microsoft.Generator.CSharp.ClientModel/test/Providers/ClientProviders/TestData/ClientProviderCustomizationTests/CanAddMethodSameName/CanAddMethodSameName.cs b/packages/http-client-csharp/generator/Microsoft.Generator.CSharp.ClientModel/test/Providers/ClientProviders/TestData/ClientProviderCustomizationTests/CanAddMethodSameName/CanAddMethodSameName.cs
new file mode 100644
index 0000000000..750bbb18f1
--- /dev/null
+++ b/packages/http-client-csharp/generator/Microsoft.Generator.CSharp.ClientModel/test/Providers/ClientProviders/TestData/ClientProviderCustomizationTests/CanAddMethodSameName/CanAddMethodSameName.cs
@@ -0,0 +1,22 @@
+// <auto-generated/>
+
+#nullable disable
+
+using System;
+using System.ClientModel;
+using System.ClientModel.Primitives;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+
+namespace Sample
+{
+    /// <summary></summary>
+    public partial class TestClient
+    {
+        public virtual ClientResult HelloAgain(string[] p1, RequestOptions options)
+        {
+
+        }
+    }
+}
diff --git a/packages/http-client-csharp/generator/Microsoft.Generator.CSharp.ClientModel/test/Providers/ClientProviders/TestData/ClientProviderCustomizationTests/CanAddMultipleMethods/CanAddMultipleMethods.cs b/packages/http-client-csharp/generator/Microsoft.Generator.CSharp.ClientModel/test/Providers/ClientProviders/TestData/ClientProviderCustomizationTests/CanAddMultipleMethods/CanAddMultipleMethods.cs
new file mode 100644
index 0000000000..17e0e7e9ff
--- /dev/null
+++ b/packages/http-client-csharp/generator/Microsoft.Generator.CSharp.ClientModel/test/Providers/ClientProviders/TestData/ClientProviderCustomizationTests/CanAddMultipleMethods/CanAddMultipleMethods.cs
@@ -0,0 +1,32 @@
+// <auto-generated/>
+
+#nullable disable
+
+using System;
+using System.ClientModel;
+using System.ClientModel.Primitives;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+
+namespace Sample
+{
+    /// <summary></summary>
+    public partial class TestClient
+    {
+        public virtual ClientResult NewMethodOne(BinaryContent content, RequestOptions options)
+        {
+            Argument.AssertNotNull(content, nameof(content));
+
+            using PipelineMessage message = CreateRequest(content, options);
+            return ClientResult.FromResponse(Pipeline.ProcessMessage(message, options));
+        }
+
+        public void NewMethodTwo() { }
+
+        public void NewMethodThree(CustomModel p1) { }
+        public bool NewMethodFour(CustomModel? p1) { return false; }
+    }
+
+    public class CustomModel { }
+}
diff --git a/packages/http-client-csharp/generator/Microsoft.Generator.CSharp.ClientModel/test/TestHelpers/MockHelpers.cs b/packages/http-client-csharp/generator/Microsoft.Generator.CSharp.ClientModel/test/TestHelpers/MockHelpers.cs
index a16c7c47e0..0c9c14cd5a 100644
--- a/packages/http-client-csharp/generator/Microsoft.Generator.CSharp.ClientModel/test/TestHelpers/MockHelpers.cs
+++ b/packages/http-client-csharp/generator/Microsoft.Generator.CSharp.ClientModel/test/TestHelpers/MockHelpers.cs
@@ -25,9 +25,13 @@ internal static class MockHelpers
         public static async Task<Mock<ClientModelPlugin>> LoadMockPluginAsync(
             Func<IReadOnlyList<InputEnumType>>? inputEnums = null,
             Func<IReadOnlyList<InputModelType>>? inputModels = null,
+            Func<IReadOnlyList<InputClient>>? clients = null,
             Func<Task<Compilation>>? compilation = null)
         {
-            var mockPlugin = LoadMockPlugin(inputEnums: inputEnums, inputModels: inputModels);
+            var mockPlugin = LoadMockPlugin(
+                inputEnums: inputEnums,
+                inputModels: inputModels,
+                clients: clients);
 
             var compilationResult = compilation == null ? null : await compilation();
 
diff --git a/packages/http-client-csharp/generator/Microsoft.Generator.CSharp/src/Providers/TypeProvider.cs b/packages/http-client-csharp/generator/Microsoft.Generator.CSharp/src/Providers/TypeProvider.cs
index 00f4b78510..d70019b3d3 100644
--- a/packages/http-client-csharp/generator/Microsoft.Generator.CSharp/src/Providers/TypeProvider.cs
+++ b/packages/http-client-csharp/generator/Microsoft.Generator.CSharp/src/Providers/TypeProvider.cs
@@ -424,7 +424,7 @@ private static bool IsMatch(TypeProvider enclosingType, MethodSignatureBase sign
 
         private static bool IsMatch(MethodSignatureBase customMethod, MethodSignatureBase method)
         {
-            if (customMethod.Parameters.Count != method.Parameters.Count)
+            if (customMethod.Parameters.Count != method.Parameters.Count || customMethod.Name != method.Name)
             {
                 return false;
             }