diff --git a/changelogs/fragments/netbox_mac_address.yml b/changelogs/fragments/netbox_mac_address.yml
new file mode 100644
index 000000000..86740c3d0
--- /dev/null
+++ b/changelogs/fragments/netbox_mac_address.yml
@@ -0,0 +1,3 @@
+minor_changes:
+  - netbox_device_interface - Add primary_mac_address option for NetBox 4.2+
+  - netbox_vm_interface - Add primary_mac_address option for NetBox 4.2+
diff --git a/meta/runtime.yml b/meta/runtime.yml
index a20a9c404..863ab2802 100644
--- a/meta/runtime.yml
+++ b/meta/runtime.yml
@@ -51,6 +51,7 @@ action_groups:
     - netbox_l2vpn
     - netbox_l2vpn_termination
     - netbox_location
+    - netbox_mac_address
     - netbox_manufacturer
     - netbox_module
     - netbox_module_bay
diff --git a/plugins/module_utils/netbox_dcim.py b/plugins/module_utils/netbox_dcim.py
index d3ede9c73..ccf1b0fc1 100644
--- a/plugins/module_utils/netbox_dcim.py
+++ b/plugins/module_utils/netbox_dcim.py
@@ -51,6 +51,7 @@
 NB_SITES = "sites"
 NB_SITE_GROUPS = "site_groups"
 NB_VIRTUAL_CHASSIS = "virtual_chassis"
+NB_MAC_ADDRESSES = "mac_addresses"
 
 try:
     from packaging.version import Version
@@ -141,6 +142,8 @@ def run(self):
             name = self.module.params["data"]["master"]
         elif data.get("slug"):
             name = data["slug"]
+        elif data.get("mac_address"):
+            name = data["mac_address"]
         elif endpoint_name == "cable":
             if self.module.params["data"]["termination_a"].get("name"):
                 termination_a_name = self.module.params["data"]["termination_a"]["name"]
diff --git a/plugins/module_utils/netbox_utils.py b/plugins/module_utils/netbox_utils.py
index ea76f43c0..08a756234 100644
--- a/plugins/module_utils/netbox_utils.py
+++ b/plugins/module_utils/netbox_utils.py
@@ -78,6 +78,7 @@
         "sites": {},
         "site_groups": {},
         "virtual_chassis": {},
+        "mac_addresses": {},
     },
     extras={
         "config_contexts": {},
@@ -226,6 +227,7 @@
     webhook="name",
     wireless_lan="ssid",
     wireless_lan_group="slug",
+    mac_address="mac_address",
 )
 
 # Specifies keys within data that need to be converted to ID and the endpoint to be used when queried
@@ -275,6 +277,7 @@
     "ipsec_profile": "ipsec_profiles",
     "location": "locations",
     "lag": "interfaces",
+    "primary_mac_address": "mac_addresses",
     "manufacturer": "manufacturers",
     "master": "devices",
     "module": "modules",
@@ -434,6 +437,7 @@
     "wireless_lans": "wireless_lan",
     "wireless_lan_groups": "wireless_lan_group",
     "wireless_links": "wireless_link",
+    "mac_addresses": "mac_address",
 }
 
 ALLOWED_QUERY_PARAMS = {
@@ -516,6 +520,7 @@
     ),
     "lag": set(["name"]),
     "location": set(["name", "slug", "site"]),
+    "mac_address": set(["mac_address"]),
     "module": set(["device", "module_bay", "module_type"]),
     "module_bay": set(["device", "name"]),
     "module_type": set(["model"]),
@@ -1414,7 +1419,7 @@ def _normalize_data(self, data):
 
         # We need to assign the correct type for the assigned object so the user doesn't have to worry about this.
         # We determine it by whether or not they pass in a device or virtual_machine
-        if data.get("assigned_object"):
+        if data.get("assigned_object") and isinstance(data["assigned_object"], dict):
             if data["assigned_object"].get("device"):
                 data["assigned_object_type"] = "dcim.interface"
             if data["assigned_object"].get("virtual_machine"):
diff --git a/plugins/modules/netbox_device_interface.py b/plugins/modules/netbox_device_interface.py
index 63980f922..42d6e73b8 100644
--- a/plugins/modules/netbox_device_interface.py
+++ b/plugins/modules/netbox_device_interface.py
@@ -86,6 +86,11 @@
           - The MAC address of the interface
         required: false
         type: str
+      primary_mac_address:
+        description:
+          - The primary MAC address of the interface (NetBox 4.2 and later)
+        required: false
+        type: str
       wwn:
         description:
           - The WWN of the interface
@@ -335,6 +340,7 @@ def main():
                     bridge=dict(required=False, type="raw"),
                     mtu=dict(required=False, type="int"),
                     mac_address=dict(required=False, type="str"),
+                    primary_mac_address=dict(required=False, type="str"),
                     wwn=dict(required=False, type="str"),
                     mgmt_only=dict(required=False, type="bool"),
                     poe_type=dict(required=False, type="raw"),
diff --git a/plugins/modules/netbox_mac_address.py b/plugins/modules/netbox_mac_address.py
new file mode 100644
index 000000000..7d70b8269
--- /dev/null
+++ b/plugins/modules/netbox_mac_address.py
@@ -0,0 +1,164 @@
+#!/usr/bin/python
+# -*- coding: utf-8 -*-
+# Copyright: (c) 2025, Martin Rødvand (@rodvand) <martin@rodvand.net>
+# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
+
+from __future__ import absolute_import, division, print_function
+
+__metaclass__ = type
+
+DOCUMENTATION = r"""
+---
+module: netbox_mac_address
+short_description: Create, update or delete MAC addresses within NetBox
+description:
+  - Creates, updates or removes MAC addresses from NetBox
+notes:
+  - Tags should be defined as a YAML list
+  - This should be ran with connection C(local) and hosts C(localhost)
+author:
+  - Martin Rødvand (@rodvand)
+requirements:
+  - pynetbox
+version_added: "3.21.0"
+extends_documentation_fragment:
+  - netbox.netbox.common
+options:
+  data:
+    type: dict
+    description:
+      - Defines the MAC address configuration
+    suboptions:
+      mac_address:
+        description:
+          - The MAC address
+        required: true
+        type: str
+      assigned_object:
+        description:
+          - The object to assign this MAC address to
+        required: false
+        type: dict
+      description:
+        description:
+          - Description of the MAC address
+        required: false
+        type: str
+      comments:
+        description:
+          - Comments for the MAC address
+        required: false
+        type: str
+      tags:
+        description:
+          - Any tags that the MAC address may need to be associated with
+        required: false
+        type: list
+        elements: raw
+      custom_fields:
+        description:
+          - Must exist in NetBox and in key/value format
+        required: false
+        type: dict
+    required: true
+"""
+
+EXAMPLES = r"""
+- name: "Test NetBox MAC address module"
+  connection: local
+  hosts: localhost
+  gather_facts: false
+
+  tasks:
+    - name: Create MAC address within NetBox with only required information
+      netbox.netbox.netbox_mac_address:
+        netbox_url: http://netbox.local
+        netbox_token: thisIsMyToken
+        data:
+          mac_address: "00:11:22:33:44:55"
+        state: present
+
+    - name: Create MAC address with interface assignment
+      netbox.netbox.netbox_mac_address:
+        netbox_url: http://netbox.local
+        netbox_token: thisIsMyToken
+        data:
+          mac_address: "AA:BB:CC:DD:EE:FF"
+          assigned_object:
+            device: Test Nexus One
+            name: Ethernet1/1
+          description: "MAC address for eth1/1"
+          tags:
+            - Network
+        state: present
+
+    - name: Delete MAC address within netbox
+      netbox.netbox.netbox_mac_address:
+        netbox_url: http://netbox.local
+        netbox_token: thisIsMyToken
+        data:
+          mac_address: "00:11:22:33:44:55"
+        state: absent
+"""
+
+RETURN = r"""
+mac_address:
+  description: Serialized object as created or already existent within NetBox
+  returned: success (when I(state=present))
+  type: dict
+msg:
+  description: Message indicating failure or info about what has been achieved
+  returned: always
+  type: str
+"""
+
+from ansible_collections.netbox.netbox.plugins.module_utils.netbox_utils import (
+    NetboxAnsibleModule,
+    NETBOX_ARG_SPEC,
+)
+from ansible_collections.netbox.netbox.plugins.module_utils.netbox_dcim import (
+    NetboxDcimModule,
+    NB_MAC_ADDRESSES,
+)
+from copy import deepcopy
+
+
+def main():
+    """
+    Main entry point for module execution
+    """
+    argument_spec = deepcopy(NETBOX_ARG_SPEC)
+    argument_spec.update(
+        dict(
+            data=dict(
+                type="dict",
+                required=True,
+                options=dict(
+                    mac_address=dict(required=True, type="str"),
+                    assigned_object=dict(required=False, type="dict"),
+                    description=dict(required=False, type="str"),
+                    comments=dict(required=False, type="str"),
+                    tags=dict(required=False, type="list", elements="raw"),
+                    custom_fields=dict(required=False, type="dict"),
+                ),
+            ),
+        )
+    )
+
+    required_if = [
+        ("state", "present", ["mac_address"]),
+        ("state", "absent", ["mac_address"]),
+    ]
+
+    module = NetboxAnsibleModule(
+        argument_spec=argument_spec,
+        supports_check_mode=True,
+        required_if=required_if,
+    )
+
+    netbox_mac_address = NetboxDcimModule(module, NB_MAC_ADDRESSES)
+    netbox_mac_address.run()
+
+
+if __name__ == "__main__":  # pragma: no cover
+    main()
diff --git a/plugins/modules/netbox_vm_interface.py b/plugins/modules/netbox_vm_interface.py
index d4bf739f2..133bfee21 100644
--- a/plugins/modules/netbox_vm_interface.py
+++ b/plugins/modules/netbox_vm_interface.py
@@ -53,6 +53,11 @@
           - The MAC address of the interface
         required: false
         type: str
+      primary_mac_address:
+        description:
+          - The primary MAC address of the interface (NetBox 4.2 and later)
+        required: false
+        type: str
       description:
         description:
           - The description of the interface
@@ -209,6 +214,7 @@ def main():
                     enabled=dict(required=False, type="bool"),
                     mtu=dict(required=False, type="int"),
                     mac_address=dict(required=False, type="str"),
+                    primary_mac_address=dict(required=False, type="str"),
                     description=dict(required=False, type="str"),
                     mode=dict(required=False, type="raw"),
                     vm_bridge=dict(required=False, type="raw"),
diff --git a/tests/integration/netbox-deploy.py b/tests/integration/netbox-deploy.py
index 68f28cb2e..af5a7b5af 100755
--- a/tests/integration/netbox-deploy.py
+++ b/tests/integration/netbox-deploy.py
@@ -372,6 +372,24 @@ def make_netbox_calls(endpoint, payload):
 ]
 created_interfaces = make_netbox_calls(nb.dcim.interfaces, dev_interfaces)
 
+# Create MAC addresses
+if nb_version >= version.parse("4.2"):
+    test100_gi1 = nb.dcim.interfaces.get(name="GigabitEthernet1", device_id=1)
+    test100_gi2 = nb.dcim.interfaces.get(name="GigabitEthernet2", device_id=1)
+    mac_addresses = [
+        {
+            "mac_address": "AA:BB:CC:DD:EE:FF",
+            "assigned_object_id": test100_gi1.id,
+            "assigned_object_type": "dcim.interface",
+        },
+        {
+            "mac_address": "AA:AB:CC:DD:EE:FF",
+            "assigned_object_id": test100_gi2.id,
+            "assigned_object_type": "dcim.interface",
+        },
+    ]
+    created_mac_addresses = make_netbox_calls(nb.dcim.mac_addresses, mac_addresses)
+
 # Wireless Interfaces
 if nb_version >= version.parse("3.1"):
     wlink_interfaces = [
diff --git a/tests/integration/targets/v4.2/tasks/main.yml b/tests/integration/targets/v4.2/tasks/main.yml
index 9b5b5c21a..33ce77bcf 100644
--- a/tests/integration/targets/v4.2/tasks/main.yml
+++ b/tests/integration/targets/v4.2/tasks/main.yml
@@ -332,15 +332,6 @@
   tags:
     - netbox_circuit
 
-- name: NETBOX_CIRCUIT_TERMINATION TESTS
-  ansible.builtin.include_tasks:
-    file: netbox_circuit_termination.yml
-    apply:
-      tags:
-        - netbox_circuit_termination
-  tags:
-    - netbox_circuit_termination
-
 - name: NETBOX_REAR_PORT TESTS
   ansible.builtin.include_tasks:
     file: netbox_rear_port.yml
@@ -732,3 +723,21 @@
         - netbox_tunnel_group
   tags:
     - netbox_tunnel_group
+
+- name: NETBOX_MAC_ADDRESS TESTS
+  ansible.builtin.include_tasks:
+    file: netbox_mac_address.yml
+    apply:
+      tags:
+        - netbox_mac_address
+  tags:
+    - netbox_mac_address
+
+- name: NETBOX_CIRCUIT_TERMINATION TESTS
+  ansible.builtin.include_tasks:
+    file: netbox_circuit_termination.yml
+    apply:
+      tags:
+        - netbox_circuit_termination
+  tags:
+    - netbox_circuit_termination
diff --git a/tests/integration/targets/v4.2/tasks/netbox_device_interface.yml b/tests/integration/targets/v4.2/tasks/netbox_device_interface.yml
index dd3c2383b..5013b6edc 100644
--- a/tests/integration/targets/v4.2/tasks/netbox_device_interface.yml
+++ b/tests/integration/targets/v4.2/tasks/netbox_device_interface.yml
@@ -310,3 +310,23 @@
       - test_twelve['interface']['name'] == "GigabitEthernet5"
       - test_twelve['interface']['device'] == 1
       - test_twelve['interface']['mark_connected'] == true
+
+- name: "13 - Update interface primary MAC address"
+  netbox.netbox.netbox_device_interface:
+    netbox_url: http://localhost:32768
+    netbox_token: "0123456789abcdef0123456789abcdef01234567"
+    data:
+      device: test100
+      name: GigabitEthernet2
+      primary_mac_address: "AA:AB:CC:DD:EE:FF"
+    state: present
+  register: test_thirteen
+
+- name: "13 - ASSERT"
+  ansible.builtin.assert:
+    that:
+      - test_thirteen is changed
+      - test_thirteen['msg'] == "interface GigabitEthernet2 updated"
+      - test_thirteen['interface']['name'] == "GigabitEthernet2"
+      - test_thirteen['interface']['device'] == 1
+      - test_thirteen['interface']['primary_mac_address'] == 2
diff --git a/tests/integration/targets/v4.2/tasks/netbox_mac_address.yml b/tests/integration/targets/v4.2/tasks/netbox_mac_address.yml
new file mode 100644
index 000000000..88192d197
--- /dev/null
+++ b/tests/integration/targets/v4.2/tasks/netbox_mac_address.yml
@@ -0,0 +1,70 @@
+---
+##
+##
+### NETBOX_MAC_ADDRESS
+##
+##
+- name: "MAC 1: Create MAC address with required parameters"
+  netbox.netbox.netbox_mac_address:
+    netbox_url: http://localhost:32768
+    netbox_token: "0123456789abcdef0123456789abcdef01234567"
+    data:
+      mac_address: "00:11:22:33:44:55"
+    state: present
+  register: test_one
+
+- name: "MAC 1: ASSERT - Create MAC address"
+  ansible.builtin.assert:
+    that:
+      - test_one is changed
+      - test_one['diff']['before']['state'] == "absent"
+      - test_one['diff']['after']['state'] == "present"
+      - test_one['mac_address']['mac_address'] == "00:11:22:33:44:55"
+      - test_one['msg'] == "mac_address 00:11:22:33:44:55 created"
+
+- name: "MAC 2: Create MAC address with all parameters"
+  netbox.netbox.netbox_mac_address:
+    netbox_url: http://localhost:32768
+    netbox_token: "0123456789abcdef0123456789abcdef01234567"
+    data:
+      mac_address: "AA:BB:CC:DD:EE:F0"
+      assigned_object:
+        device: Test Nexus One
+        name: Ethernet1/1
+      description: "Test MAC address"
+      comments: "Test MAC address comment"
+      tags:
+        - Schnozzberry
+    state: present
+  register: test_two
+
+- name: "MAC 2: ASSERT - Create MAC address with all parameters"
+  ansible.builtin.assert:
+    that:
+      - test_two is changed
+      - test_two['diff']['before']['state'] == "absent"
+      - test_two['diff']['after']['state'] == "present"
+      - test_two['mac_address']['mac_address'] == "AA:BB:CC:DD:EE:F0"
+      - test_two['mac_address']['assigned_object_type'] == "dcim.interface"
+      - test_two['mac_address']['assigned_object_id'] == 1
+      - test_two['mac_address']['description'] == "Test MAC address"
+      - test_two['mac_address']['comments'] == "Test MAC address comment"
+      - test_two['mac_address']['tags'][0] == 4
+      - test_two['msg'] == "mac_address AA:BB:CC:DD:EE:F0 created"
+
+- name: "MAC 3: Delete MAC address"
+  netbox.netbox.netbox_mac_address:
+    netbox_url: http://localhost:32768
+    netbox_token: "0123456789abcdef0123456789abcdef01234567"
+    data:
+      mac_address: "00:11:22:33:44:55"
+    state: absent
+  register: test_three
+
+- name: "MAC 3: ASSERT - Delete MAC address"
+  ansible.builtin.assert:
+    that:
+      - test_three is changed
+      - test_three['diff']['before']['state'] == "present"
+      - test_three['diff']['after']['state'] == "absent"
+      - test_three['msg'] == "mac_address 00:11:22:33:44:55 deleted"