diff --git a/helpdesk/tests/test_api.py b/helpdesk/tests/test_api.py
new file mode 100644
index 00000000..3213509b
--- /dev/null
+++ b/helpdesk/tests/test_api.py
@@ -0,0 +1,262 @@
+import base64
+from datetime import datetime
+
+from django.contrib.auth.models import User
+from pytz import UTC
+from rest_framework import HTTP_HEADER_ENCODING
+from rest_framework.exceptions import ErrorDetail
+from rest_framework.status import HTTP_201_CREATED, HTTP_200_OK, HTTP_204_NO_CONTENT, HTTP_400_BAD_REQUEST
+from rest_framework.test import APITestCase
+
+from helpdesk.models import Queue, Ticket, CustomField
+
+
+class TicketTest(APITestCase):
+    @classmethod
+    def setUpTestData(cls):
+        cls.queue = Queue.objects.create(
+            title='Test Queue',
+            slug='test-queue',
+        )
+
+    def test_create_api_ticket_not_authenticated_user(self):
+        response = self.client.post('/api/tickets/')
+        self.assertEqual(response.status_code, 403)
+
+    def test_create_api_ticket_authenticated_non_staff_user(self):
+        non_staff_user = User.objects.create_user(username='test')
+        self.client.force_authenticate(non_staff_user)
+        response = self.client.post('/api/tickets/')
+        self.assertEqual(response.status_code, 403)
+
+    def test_create_api_ticket_no_data(self):
+        staff_user = User.objects.create_user(username='test', is_staff=True)
+        self.client.force_authenticate(staff_user)
+        response = self.client.post('/api/tickets/')
+        self.assertEqual(response.status_code, HTTP_400_BAD_REQUEST)
+        self.assertEqual(response.data, {
+            'queue': [ErrorDetail(string='This field is required.', code='required')],
+            'title': [ErrorDetail(string='This field is required.', code='required')]
+        })
+        self.assertFalse(Ticket.objects.exists())
+
+    def test_create_api_ticket_wrong_date_format(self):
+        staff_user = User.objects.create_user(username='test', is_staff=True)
+        self.client.force_authenticate(staff_user)
+        response = self.client.post('/api/tickets/', {
+            'queue': self.queue.id,
+            'title': 'Test title',
+            'due_date': 'monday, 1st of may 2022'
+        })
+        self.assertEqual(response.status_code, HTTP_400_BAD_REQUEST)
+        self.assertEqual(response.data, {
+            'due_date': [ErrorDetail(string='Datetime has wrong format. Use one of these formats instead: YYYY-MM-DDThh:mm[:ss[.uuuuuu]][+HH:MM|-HH:MM|Z].', code='invalid')]
+        })
+        self.assertFalse(Ticket.objects.exists())
+
+    def test_create_api_ticket_authenticated_staff_user(self):
+        staff_user = User.objects.create_user(username='test', is_staff=True)
+        self.client.force_authenticate(staff_user)
+        response = self.client.post('/api/tickets/', {
+            'queue': self.queue.id,
+            'title': 'Test title',
+            'description': 'Test description\nMulti lines',
+            'submitter_email': 'test@mail.com',
+            'priority': 4
+        })
+        self.assertEqual(response.status_code, HTTP_201_CREATED)
+        created_ticket = Ticket.objects.get()
+        self.assertEqual(created_ticket.title, 'Test title')
+        self.assertEqual(created_ticket.description, 'Test description\nMulti lines')
+        self.assertEqual(created_ticket.submitter_email, 'test@mail.com')
+        self.assertEqual(created_ticket.priority, 4)
+
+    def test_create_api_ticket_with_basic_auth(self):
+        username = 'admin'
+        password = 'admin'
+        User.objects.create_user(username=username, password=password, is_staff=True)
+
+        test_user = User.objects.create_user(username='test')
+        merge_ticket = Ticket.objects.create(queue=self.queue, title='merge ticket')
+
+        # Generate base64 credentials string
+        credentials = f"{username}:{password}"
+        base64_credentials = base64.b64encode(credentials.encode(HTTP_HEADER_ENCODING)).decode(HTTP_HEADER_ENCODING)
+
+        self.client.credentials(HTTP_AUTHORIZATION=f"Basic {base64_credentials}")
+        response = self.client.post(
+            '/api/tickets/',
+            {
+                'queue': self.queue.id,
+                'title': 'Title',
+                'description': 'Description',
+                'resolution': 'Resolution',
+                'assigned_to': test_user.id,
+                'submitter_email': 'test@mail.com',
+                'status': Ticket.RESOLVED_STATUS,
+                'priority': 1,
+                'on_hold': True,
+                'due_date': datetime(2022, 4, 10, 15, 6),
+                'merged_to': merge_ticket.id
+            }
+        )
+
+        self.assertEqual(response.status_code, HTTP_201_CREATED)
+        created_ticket = Ticket.objects.last()
+        self.assertEqual(created_ticket.title, 'Title')
+        self.assertEqual(created_ticket.description, 'Description')
+        self.assertIsNone(created_ticket.resolution)  # resolution can not be set on creation
+        self.assertEqual(created_ticket.assigned_to, test_user)
+        self.assertEqual(created_ticket.submitter_email, 'test@mail.com')
+        self.assertEqual(created_ticket.priority, 1)
+        self.assertFalse(created_ticket.on_hold)
+        self.assertEqual(created_ticket.status, Ticket.OPEN_STATUS)  # status is always open on creation
+        self.assertEqual(created_ticket.due_date, datetime(2022, 4, 10, 15, 6, tzinfo=UTC))
+        self.assertIsNone(created_ticket.merged_to)
+
+    def test_edit_api_ticket(self):
+        staff_user = User.objects.create_user(username='admin', is_staff=True)
+        test_ticket = Ticket.objects.create(queue=self.queue, title='Test ticket')
+
+        test_user = User.objects.create_user(username='test')
+        merge_ticket = Ticket.objects.create(queue=self.queue, title='merge ticket')
+
+        self.client.force_authenticate(staff_user)
+        response = self.client.put(
+            '/api/tickets/%d/' % test_ticket.id,
+            {
+                'queue': self.queue.id,
+                'title': 'Title',
+                'description': 'Description',
+                'resolution': 'Resolution',
+                'assigned_to': test_user.id,
+                'submitter_email': 'test@mail.com',
+                'status': Ticket.RESOLVED_STATUS,
+                'priority': 1,
+                'on_hold': True,
+                'due_date': datetime(2022, 4, 10, 15, 6),
+                'merged_to': merge_ticket.id
+            }
+        )
+
+        self.assertEqual(response.status_code, HTTP_200_OK)
+        test_ticket.refresh_from_db()
+        self.assertEqual(test_ticket.title, 'Title')
+        self.assertEqual(test_ticket.description, 'Description')
+        self.assertEqual(test_ticket.resolution, 'Resolution')
+        self.assertEqual(test_ticket.assigned_to, test_user)
+        self.assertEqual(test_ticket.submitter_email, 'test@mail.com')
+        self.assertEqual(test_ticket.priority, 1)
+        self.assertTrue(test_ticket.on_hold)
+        self.assertEqual(test_ticket.status, Ticket.RESOLVED_STATUS)
+        self.assertEqual(test_ticket.due_date, datetime(2022, 4, 10, 15, 6, tzinfo=UTC))
+        self.assertEqual(test_ticket.merged_to, merge_ticket)
+
+    def test_partial_edit_api_ticket(self):
+        staff_user = User.objects.create_user(username='admin', is_staff=True)
+        test_ticket = Ticket.objects.create(queue=self.queue, title='Test ticket')
+
+        self.client.force_authenticate(staff_user)
+        response = self.client.patch(
+            '/api/tickets/%d/' % test_ticket.id,
+            {
+                'description': 'New description',
+            }
+        )
+
+        self.assertEqual(response.status_code, HTTP_200_OK)
+        test_ticket.refresh_from_db()
+        self.assertEqual(test_ticket.description, 'New description')
+
+    def test_delete_api_ticket(self):
+        staff_user = User.objects.create_user(username='admin', is_staff=True)
+        test_ticket = Ticket.objects.create(queue=self.queue, title='Test ticket')
+        self.client.force_authenticate(staff_user)
+        response = self.client.delete('/api/tickets/%d/' % test_ticket.id)
+        self.assertEqual(response.status_code, HTTP_204_NO_CONTENT)
+        self.assertFalse(Ticket.objects.exists())
+
+    def test_create_api_ticket_with_custom_fields(self):
+        # Create custom fields
+        for field_type, field_display in CustomField.DATA_TYPE_CHOICES:
+            extra_data = {}
+            if field_type in ('varchar', 'text'):
+                extra_data['max_length'] = 10
+            if field_type == 'integer':
+                # Set one field as required to test error if not provided
+                extra_data['required'] = True
+            if field_type == 'decimal':
+                extra_data['max_length'] = 7
+                extra_data['decimal_places'] = 3
+            if field_type == 'list':
+                extra_data['list_values'] = '''Green
+                Blue
+                Red
+                Yellow'''
+            CustomField.objects.create(name=field_type, label=field_display, data_type=field_type, **extra_data)
+
+        staff_user = User.objects.create_user(username='test', is_staff=True)
+        self.client.force_authenticate(staff_user)
+
+        # Test creation without providing required field
+        response = self.client.post('/api/tickets/', {
+            'queue': self.queue.id,
+            'title': 'Test title',
+            'description': 'Test description\nMulti lines',
+            'submitter_email': 'test@mail.com',
+            'priority': 4
+        })
+        self.assertEqual(response.status_code, HTTP_400_BAD_REQUEST)
+        self.assertEqual(response.data, {'custom_integer': [ErrorDetail(string='This field is required.', code='required')]})
+
+        # Test creation with custom field values
+        response = self.client.post('/api/tickets/', {
+            'queue': self.queue.id,
+            'title': 'Test title',
+            'description': 'Test description\nMulti lines',
+            'submitter_email': 'test@mail.com',
+            'priority': 4,
+            'custom_varchar': 'test',
+            'custom_text': 'multi\nline',
+            'custom_integer': '1',
+            'custom_decimal': '42.987',
+            'custom_list': 'Red',
+            'custom_boolean': True,
+            'custom_date': '2022-4-11',
+            'custom_time': '23:59:59',
+            'custom_datetime': '2022-4-10 18:27',
+            'custom_email': 'email@test.com',
+            'custom_url': 'http://django-helpdesk.readthedocs.org/',
+            'custom_ipaddress': '127.0.0.1',
+            'custom_slug': 'test-slug',
+        })
+        self.assertEqual(response.status_code, HTTP_201_CREATED)
+        # Check all fields with data returned from the response
+        self.assertEqual(response.data, {
+            'id': 1,
+            'queue': 1,
+            'title': 'Test title',
+            'description': 'Test description\nMulti lines',
+            'resolution': None,
+            'submitter_email': 'test@mail.com',
+            'assigned_to': None,
+            'status': 1,
+            'on_hold': False,
+            'priority': 4,
+            'due_date': None,
+            'merged_to': None,
+            'custom_varchar': 'test',
+            'custom_text': 'multi\nline',
+            'custom_integer': 1,
+            'custom_decimal': '42.987',
+            'custom_list': 'Red',
+            'custom_boolean': True,
+            'custom_date': '2022-04-11',
+            'custom_time': '23:59:59',
+            'custom_datetime': '2022-04-10T18:27',
+            'custom_email': 'email@test.com',
+            'custom_url': 'http://django-helpdesk.readthedocs.org/',
+            'custom_ipaddress': '127.0.0.1',
+            'custom_slug': 'test-slug'
+        })
+