diff --git a/pkg/controller/endpointslicemirroring/reconciler.go b/pkg/controller/endpointslicemirroring/reconciler.go
index 15f991eecbd..2fa83bde2fb 100644
--- a/pkg/controller/endpointslicemirroring/reconciler.go
+++ b/pkg/controller/endpointslicemirroring/reconciler.go
@@ -29,6 +29,7 @@ import (
 	clientset "k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/tools/record"
 	"k8s.io/klog/v2"
+	endpointsv1 "k8s.io/kubernetes/pkg/api/v1/endpoints"
 	"k8s.io/kubernetes/pkg/controller/endpointslicemirroring/metrics"
 	endpointutil "k8s.io/kubernetes/pkg/controller/util/endpoint"
 	endpointsliceutil "k8s.io/kubernetes/pkg/controller/util/endpointslice"
@@ -68,7 +69,9 @@ func (r *reconciler) reconcile(endpoints *corev1.Endpoints, existingSlices []*di
 	numInvalidAddresses := 0
 	addressesSkipped := 0
 
-	for _, subset := range endpoints.Subsets {
+	// canonicalize the Endpoints subsets before processing them
+	subsets := endpointsv1.RepackSubsets(endpoints.Subsets)
+	for _, subset := range subsets {
 		multiKey := d.initPorts(subset.Ports)
 
 		totalAddresses := len(subset.Addresses) + len(subset.NotReadyAddresses)
diff --git a/pkg/controller/endpointslicemirroring/reconciler_test.go b/pkg/controller/endpointslicemirroring/reconciler_test.go
index 36f405307ec..4818863f6fc 100644
--- a/pkg/controller/endpointslicemirroring/reconciler_test.go
+++ b/pkg/controller/endpointslicemirroring/reconciler_test.go
@@ -28,6 +28,7 @@ import (
 	"k8s.io/client-go/kubernetes/scheme"
 	"k8s.io/client-go/tools/record"
 	"k8s.io/component-base/metrics/testutil"
+	endpointsv1 "k8s.io/kubernetes/pkg/api/v1/endpoints"
 	"k8s.io/kubernetes/pkg/controller/endpointslicemirroring/metrics"
 	endpointsliceutil "k8s.io/kubernetes/pkg/controller/util/endpointslice"
 	"k8s.io/utils/pointer"
@@ -90,6 +91,102 @@ func TestReconcile(t *testing.T) {
 		expectedNumSlices:      1,
 		expectedClientActions:  1,
 		expectedMetrics:        &expectedMetrics{desiredSlices: 1, actualSlices: 1, desiredEndpoints: 1, addedPerSync: 1, numCreated: 1},
+	}, {
+		testName: "Endpoints with 2 subset, different port and address",
+		subsets: []corev1.EndpointSubset{
+			{
+				Ports: []corev1.EndpointPort{{
+					Name:     "http",
+					Port:     80,
+					Protocol: corev1.ProtocolTCP,
+				}},
+				Addresses: []corev1.EndpointAddress{{
+					IP:       "10.0.0.1",
+					Hostname: "pod-1",
+					NodeName: pointer.String("node-1"),
+				}},
+			},
+			{
+				Ports: []corev1.EndpointPort{{
+					Name:     "https",
+					Port:     443,
+					Protocol: corev1.ProtocolTCP,
+				}},
+				Addresses: []corev1.EndpointAddress{{
+					IP:       "10.0.0.2",
+					Hostname: "pod-2",
+					NodeName: pointer.String("node-1"),
+				}},
+			},
+		},
+		existingEndpointSlices: []*discovery.EndpointSlice{},
+		expectedNumSlices:      2,
+		expectedClientActions:  2,
+		expectedMetrics:        &expectedMetrics{desiredSlices: 2, actualSlices: 2, desiredEndpoints: 2, addedPerSync: 2, numCreated: 2},
+	}, {
+		testName: "Endpoints with 2 subset, different port and same address",
+		subsets: []corev1.EndpointSubset{
+			{
+				Ports: []corev1.EndpointPort{{
+					Name:     "http",
+					Port:     80,
+					Protocol: corev1.ProtocolTCP,
+				}},
+				Addresses: []corev1.EndpointAddress{{
+					IP:       "10.0.0.1",
+					Hostname: "pod-1",
+					NodeName: pointer.String("node-1"),
+				}},
+			},
+			{
+				Ports: []corev1.EndpointPort{{
+					Name:     "https",
+					Port:     443,
+					Protocol: corev1.ProtocolTCP,
+				}},
+				Addresses: []corev1.EndpointAddress{{
+					IP:       "10.0.0.1",
+					Hostname: "pod-1",
+					NodeName: pointer.String("node-1"),
+				}},
+			},
+		},
+		existingEndpointSlices: []*discovery.EndpointSlice{},
+		expectedNumSlices:      1,
+		expectedClientActions:  1,
+		expectedMetrics:        &expectedMetrics{desiredSlices: 1, actualSlices: 1, desiredEndpoints: 1, addedPerSync: 1, numCreated: 1},
+	}, {
+		testName: "Endpoints with 2 subset, different address and same port",
+		subsets: []corev1.EndpointSubset{
+			{
+				Ports: []corev1.EndpointPort{{
+					Name:     "http",
+					Port:     80,
+					Protocol: corev1.ProtocolTCP,
+				}},
+				Addresses: []corev1.EndpointAddress{{
+					IP:       "10.0.0.1",
+					Hostname: "pod-1",
+					NodeName: pointer.String("node-1"),
+				}},
+			},
+			{
+				Ports: []corev1.EndpointPort{{
+					Name:     "http",
+					Port:     80,
+					Protocol: corev1.ProtocolTCP,
+				}},
+				Addresses: []corev1.EndpointAddress{{
+					IP:       "10.0.0.2",
+					Hostname: "pod-2",
+					NodeName: pointer.String("node-1"),
+				}},
+			},
+		},
+		existingEndpointSlices: []*discovery.EndpointSlice{},
+		expectedNumSlices:      1,
+		expectedClientActions:  1,
+		expectedMetrics:        &expectedMetrics{desiredSlices: 1, actualSlices: 1, desiredEndpoints: 2, addedPerSync: 2, numCreated: 1},
 	}, {
 		testName: "Endpoints with 1 subset, port, and address, pending deletion",
 		subsets: []corev1.EndpointSubset{{
@@ -1015,7 +1112,10 @@ func expectEndpointSlices(t *testing.T, num, maxEndpointsPerSubset int, endpoint
 		}
 	}
 
-	for _, epSubset := range endpoints.Subsets {
+	// canonicalize endpoints to match the expected endpoints, otherwise the test
+	// that creates more endpoints than allowed fail becaused the list of final
+	// endpoints doesn't match.
+	for _, epSubset := range endpointsv1.RepackSubsets(endpoints.Subsets) {
 		if len(epSubset.Addresses) == 0 && len(epSubset.NotReadyAddresses) == 0 {
 			continue
 		}
diff --git a/test/e2e/network/endpointslicemirroring.go b/test/e2e/network/endpointslicemirroring.go
index 3c4104b26f6..d74792e0da8 100644
--- a/test/e2e/network/endpointslicemirroring.go
+++ b/test/e2e/network/endpointslicemirroring.go
@@ -19,6 +19,7 @@ package network
 import (
 	"context"
 	"fmt"
+	"net"
 	"time"
 
 	"github.com/onsi/ginkgo/v2"
@@ -28,6 +29,7 @@ import (
 	"k8s.io/apimachinery/pkg/util/wait"
 	clientset "k8s.io/client-go/kubernetes"
 	"k8s.io/kubernetes/test/e2e/framework"
+	e2epod "k8s.io/kubernetes/test/e2e/framework/pod"
 	"k8s.io/kubernetes/test/e2e/network/common"
 	admissionapi "k8s.io/pod-security-admission/api"
 )
@@ -199,4 +201,135 @@ var _ = common.SIGDescribe("EndpointSliceMirroring", func() {
 			}
 		})
 	})
+
+	ginkgo.It("should mirror a custom Endpoint with multiple subsets and same IP address", func() {
+		ns := f.Namespace.Name
+		svc := createServiceReportErr(cs, f.Namespace.Name, &v1.Service{
+			ObjectMeta: metav1.ObjectMeta{
+				Name: "example-custom-endpoints",
+			},
+			Spec: v1.ServiceSpec{
+				Ports: []v1.ServicePort{
+					{
+						Name:     "port80",
+						Port:     80,
+						Protocol: v1.ProtocolTCP,
+					},
+					{
+						Name:     "port81",
+						Port:     81,
+						Protocol: v1.ProtocolTCP,
+					},
+				},
+			},
+		})
+
+		// Add a backend pod to the service in the other node
+		port8080 := []v1.ContainerPort{
+			{
+				ContainerPort: 8090,
+				Protocol:      v1.ProtocolTCP,
+			},
+		}
+		port9090 := []v1.ContainerPort{
+			{
+				ContainerPort: 9090,
+				Protocol:      v1.ProtocolTCP,
+			},
+		}
+
+		serverPod := e2epod.NewAgnhostPodFromContainers(
+			"", "pod-handle-http-request", nil,
+			e2epod.NewAgnhostContainer("container-handle-8090-request", nil, port8080, "netexec", "--http-port", "8090", "--udp-port", "-1"),
+			e2epod.NewAgnhostContainer("container-handle-9090-request", nil, port9090, "netexec", "--http-port", "9090", "--udp-port", "-1"),
+		)
+
+		pod := e2epod.NewPodClient(f).CreateSync(serverPod)
+
+		if pod.Status.PodIP == "" {
+			framework.Failf("PodIP not assigned for pod %s", pod.Name)
+		}
+
+		// create custom endpoints
+		endpoints := &v1.Endpoints{
+			ObjectMeta: metav1.ObjectMeta{
+				Name: svc.Name,
+			},
+			Subsets: []v1.EndpointSubset{
+				{
+					Ports: []v1.EndpointPort{{
+						Name: "port80",
+						Port: 8090,
+					}},
+					Addresses: []v1.EndpointAddress{{
+						IP: pod.Status.PodIP,
+					}},
+				},
+				{
+					Ports: []v1.EndpointPort{{
+						Name: "port81",
+						Port: 9090,
+					}},
+					Addresses: []v1.EndpointAddress{{
+						IP: pod.Status.PodIP,
+					}},
+				},
+			},
+		}
+
+		ginkgo.By("mirroring a new custom Endpoint", func() {
+			_, err := cs.CoreV1().Endpoints(f.Namespace.Name).Create(context.TODO(), endpoints, metav1.CreateOptions{})
+			framework.ExpectNoError(err, "Unexpected error creating Endpoints")
+
+			if err := wait.PollImmediate(2*time.Second, 12*time.Second, func() (bool, error) {
+				esList, err := cs.DiscoveryV1().EndpointSlices(f.Namespace.Name).List(context.TODO(), metav1.ListOptions{
+					LabelSelector: discoveryv1.LabelServiceName + "=" + svc.Name,
+				})
+				if err != nil {
+					framework.Logf("Error listing EndpointSlices: %v", err)
+					return false, nil
+				}
+				if len(esList.Items) == 0 {
+					framework.Logf("Waiting for at least 1 EndpointSlice to exist, got %d", len(esList.Items))
+					return false, nil
+				}
+				return true, nil
+			}); err != nil {
+				framework.Failf("Did not find matching EndpointSlice for %s/%s: %s", svc.Namespace, svc.Name, err)
+			}
+		})
+
+		// connect to the service must work
+		ginkgo.By("Creating a pause pods that will try to connect to the webservers")
+		pausePod := e2epod.NewAgnhostPod(ns, "pause-pod-0", nil, nil, nil)
+		e2epod.NewPodClient(f).CreateSync(pausePod)
+		dest1 := net.JoinHostPort(svc.Spec.ClusterIP, "80")
+		dest2 := net.JoinHostPort(svc.Spec.ClusterIP, "81")
+		execHostnameTest(*pausePod, dest1, pod.Name)
+		execHostnameTest(*pausePod, dest2, pod.Name)
+
+		// delete custom endpoints and wait until the endpoint slices are deleted too
+		ginkgo.By("mirroring deletion of a custom Endpoint", func() {
+			err := cs.CoreV1().Endpoints(f.Namespace.Name).Delete(context.TODO(), endpoints.Name, metav1.DeleteOptions{})
+			framework.ExpectNoError(err, "Unexpected error deleting Endpoints")
+
+			// Expect mirrored EndpointSlice resource to be updated.
+			if err := wait.PollImmediate(2*time.Second, 12*time.Second, func() (bool, error) {
+				esList, err := cs.DiscoveryV1().EndpointSlices(f.Namespace.Name).List(context.TODO(), metav1.ListOptions{
+					LabelSelector: discoveryv1.LabelServiceName + "=" + svc.Name,
+				})
+				if err != nil {
+					return false, err
+				}
+				if len(esList.Items) != 0 {
+					framework.Logf("Waiting for 0 EndpointSlices to exist, got %d", len(esList.Items))
+					return false, nil
+				}
+
+				return true, nil
+			}); err != nil {
+				framework.Failf("Did not find matching EndpointSlice for %s/%s: %s", svc.Namespace, svc.Name, err)
+			}
+		})
+	})
 })
diff --git a/test/integration/endpointslice/endpointslicemirroring_test.go b/test/integration/endpointslice/endpointslicemirroring_test.go
index be71e60e4fa..89ac76521f4 100644
--- a/test/integration/endpointslice/endpointslicemirroring_test.go
+++ b/test/integration/endpointslice/endpointslicemirroring_test.go
@@ -86,7 +86,7 @@ func TestEndpointSliceMirroring(t *testing.T) {
 		testName                     string
 		service                      *corev1.Service
 		customEndpoints              *corev1.Endpoints
-		expectEndpointSlice          bool
+		expectEndpointSlice          int
 		expectEndpointSliceManagedBy string
 	}{{
 		testName: "Service with selector",
@@ -103,7 +103,7 @@ func TestEndpointSliceMirroring(t *testing.T) {
 				},
 			},
 		},
-		expectEndpointSlice:          true,
+		expectEndpointSlice:          1,
 		expectEndpointSliceManagedBy: "endpointslice-controller.k8s.io",
 	}, {
 		testName: "Service without selector",
@@ -130,7 +130,85 @@ func TestEndpointSliceMirroring(t *testing.T) {
 				}},
 			}},
 		},
-		expectEndpointSlice:          true,
+		expectEndpointSlice:          1,
+		expectEndpointSliceManagedBy: "endpointslicemirroring-controller.k8s.io",
+	}, {
+		testName: "Service without selector Endpoint multiple subsets and same address",
+		service: &corev1.Service{
+			ObjectMeta: metav1.ObjectMeta{
+				Name: "test-123",
+			},
+			Spec: corev1.ServiceSpec{
+				Ports: []corev1.ServicePort{{
+					Port: int32(80),
+				}},
+			},
+		},
+		customEndpoints: &corev1.Endpoints{
+			ObjectMeta: metav1.ObjectMeta{
+				Name: "test-123",
+			},
+			Subsets: []corev1.EndpointSubset{
+				{
+					Ports: []corev1.EndpointPort{{
+						Name: "port1",
+						Port: 80,
+					}},
+					Addresses: []corev1.EndpointAddress{{
+						IP: "10.0.0.1",
+					}},
+				},
+				{
+					Ports: []corev1.EndpointPort{{
+						Name: "port2",
+						Port: 90,
+					}},
+					Addresses: []corev1.EndpointAddress{{
+						IP: "10.0.0.1",
+					}},
+				},
+			},
+		},
+		expectEndpointSlice:          1,
+		expectEndpointSliceManagedBy: "endpointslicemirroring-controller.k8s.io",
+	}, {
+		testName: "Service without selector Endpoint multiple subsets",
+		service: &corev1.Service{
+			ObjectMeta: metav1.ObjectMeta{
+				Name: "test-123",
+			},
+			Spec: corev1.ServiceSpec{
+				Ports: []corev1.ServicePort{{
+					Port: int32(80),
+				}},
+			},
+		},
+		customEndpoints: &corev1.Endpoints{
+			ObjectMeta: metav1.ObjectMeta{
+				Name: "test-123",
+			},
+			Subsets: []corev1.EndpointSubset{
+				{
+					Ports: []corev1.EndpointPort{{
+						Name: "port1",
+						Port: 80,
+					}},
+					Addresses: []corev1.EndpointAddress{{
+						IP: "10.0.0.1",
+					}},
+				},
+				{
+					Ports: []corev1.EndpointPort{{
+						Name: "port2",
+						Port: 90,
+					}},
+					Addresses: []corev1.EndpointAddress{{
+						IP: "10.0.0.2",
+					}},
+				},
+			},
+		},
+		expectEndpointSlice:          2,
 		expectEndpointSliceManagedBy: "endpointslicemirroring-controller.k8s.io",
 	}, {
 		testName: "Service without Endpoints",
@@ -148,7 +226,7 @@ func TestEndpointSliceMirroring(t *testing.T) {
 			},
 		},
 		customEndpoints:              nil,
-		expectEndpointSlice:          true,
+		expectEndpointSlice:          1,
 		expectEndpointSliceManagedBy: "endpointslice-controller.k8s.io",
 	}, {
 		testName: "Endpoints without Service",
@@ -166,7 +244,7 @@ func TestEndpointSliceMirroring(t *testing.T) {
 				}},
 			}},
 		},
-		expectEndpointSlice: false,
+		expectEndpointSlice: 0,
 	}}
 
 	for i, tc := range testCases {
@@ -201,13 +279,13 @@ func TestEndpointSliceMirroring(t *testing.T) {
 					return false, err
 				}
 
-				if tc.expectEndpointSlice {
-					if len(esList.Items) == 0 {
+				if tc.expectEndpointSlice > 0 {
+					if len(esList.Items) < tc.expectEndpointSlice {
 						t.Logf("Waiting for EndpointSlice to be created")
 						return false, nil
 					}
-					if len(esList.Items) > 1 {
-						return false, fmt.Errorf("Only expected 1 EndpointSlice, got %d", len(esList.Items))
+					if len(esList.Items) != tc.expectEndpointSlice {
+						return false, fmt.Errorf("Only expected %d EndpointSlice, got %d", tc.expectEndpointSlice, len(esList.Items))
 					}
 					endpointSlice := esList.Items[0]
 					if tc.expectEndpointSliceManagedBy != "" {