diff --git a/src/Microsoft.AspNet.Hosting/Internal/WebApplication.cs b/src/Microsoft.AspNet.Hosting/Internal/WebApplication.cs
index 170a7f26cd..74e95c4bc5 100644
--- a/src/Microsoft.AspNet.Hosting/Internal/WebApplication.cs
+++ b/src/Microsoft.AspNet.Hosting/Internal/WebApplication.cs
@@ -21,9 +21,6 @@ namespace Microsoft.AspNet.Hosting.Internal
 {
     public class WebApplication : IWebApplication
     {
-        // This is defined by IIS's HttpPlatformHandler.
-        private static readonly string ServerPort = "HTTP_PLATFORM_PORT";
-
         private readonly IServiceCollection _applicationServiceCollection;
         private readonly IStartupLoader _startupLoader;
         private readonly ApplicationLifetime _applicationLifetime;
@@ -223,19 +220,10 @@ namespace Microsoft.AspNet.Hosting.Internal
 
                 Server = ServerFactory.CreateServer(_config);
                 var addresses = Server.Features?.Get<IServerAddressesFeature>()?.Addresses;
-                if (addresses != null && !addresses.IsReadOnly)
+                if (addresses != null && !addresses.IsReadOnly && addresses.Count == 0)
                 {
-                    var port = _config[ServerPort];
-                    if (!string.IsNullOrEmpty(port))
-                    {
-                        addresses.Add("http://localhost:" + port);
-                    }
-
                     // Provide a default address if there aren't any configured.
-                    if (addresses.Count == 0)
-                    {
-                        addresses.Add("http://localhost:5000");
-                    }
+                    addresses.Add("http://localhost:5000");
                 }
             }
         }
diff --git a/test/Microsoft.AspNet.Hosting.Tests/WebApplicationTests.cs b/test/Microsoft.AspNet.Hosting.Tests/WebApplicationTests.cs
index fcbb01736a..a83818a9cf 100644
--- a/test/Microsoft.AspNet.Hosting.Tests/WebApplicationTests.cs
+++ b/test/Microsoft.AspNet.Hosting.Tests/WebApplicationTests.cs
@@ -106,24 +106,6 @@ namespace Microsoft.AspNet.Hosting
             Assert.NotNull(application.Services.GetService<IHostingEnvironment>());
         }
 
-        [Fact]
-        public void CanSpecifyPortConfig()
-        {
-            var vals = new Dictionary<string, string>
-            {
-                { "Server", "Microsoft.AspNet.Hosting.Tests" },
-                { "HTTP_PLATFORM_PORT", "abc123" }
-            };
-
-            var builder = new ConfigurationBuilder()
-                .AddInMemoryCollection(vals);
-            var config = builder.Build();
-            var application = CreateBuilder(config).Build();
-            application.Start();
-            Assert.NotNull(application.Services.GetService<IHostingEnvironment>());
-            Assert.Equal("http://localhost:abc123", application.ServerFeatures.Get<IServerAddressesFeature>().Addresses.First());
-        }
-
         [Fact]
         public void CanDefaultAddresseIfNotConfigured()
         {