diff --git a/swh/lister/gitlab/lister.py b/swh/lister/gitlab/lister.py
--- a/swh/lister/gitlab/lister.py
+++ b/swh/lister/gitlab/lister.py
@@ -5,6 +5,7 @@
 
 from dataclasses import asdict, dataclass
 import logging
+import random
 from typing import Any, Dict, Iterator, Optional, Tuple
 from urllib.parse import parse_qs, urlparse
 
@@ -93,7 +94,7 @@
     def __init__(
         self,
         scheduler,
-        url=None,
+        url: str,
         instance: Optional[str] = None,
         credentials: Optional[CredentialsType] = None,
         incremental: bool = False,
@@ -101,10 +102,7 @@
         if instance is None:
             instance = parse_url(url).host
         super().__init__(
-            scheduler=scheduler,
-            credentials=None,  # anonymous for now
-            url=url,
-            instance=instance,
+            scheduler=scheduler, url=url, instance=instance, credentials=credentials,
         )
         self.incremental = incremental
         self.last_page: Optional[str] = None
@@ -114,12 +112,24 @@
             {"Accept": "application/json", "User-Agent": USER_AGENT}
         )
 
+        if len(self.credentials) > 0:
+            cred = random.choice(self.credentials)
+            logger.warning(
+                "Using %s credentials from user %s", self.instance, cred["username"]
+            )
+            self.set_credentials(cred["username"], cred["password"])
+
     def state_from_dict(self, d: Dict[str, Any]) -> GitLabListerState:
         return GitLabListerState(**d)
 
     def state_to_dict(self, state: GitLabListerState) -> Dict[str, Any]:
         return asdict(state)
 
+    def set_credentials(self, username: Optional[str], password: Optional[str]) -> None:
+        """Set basic authentication headers with given credentials."""
+        if username is not None and password is not None:
+            self.session.auth = (username, password)
+
     @throttling_retry(
         retry=_if_rate_limited, before_sleep=before_sleep_log(logger, logging.WARNING)
     )
diff --git a/swh/lister/gitlab/tests/test_lister.py b/swh/lister/gitlab/tests/test_lister.py
--- a/swh/lister/gitlab/tests/test_lister.py
+++ b/swh/lister/gitlab/tests/test_lister.py
@@ -198,6 +198,19 @@
     assert_sleep_calls(mocker, mock_sleep, [1, WAIT_EXP_BASE])
 
 
+def test_lister_gitlab_credentials(swh_scheduler):
+    """Gitlab lister supports credentials configuration
+
+    """
+    instance = "gitlab"
+    credentials = {"gitlab": {instance: [{"username": "u", "password": "p"}]}}
+    url = api_url(instance)
+    lister = GitLabLister(
+        scheduler=swh_scheduler, url=url, instance=instance, credentials=credentials
+    )
+    assert lister.session.auth == ("u", "p")
+
+
 @pytest.mark.parametrize(
     "url,expected_result",
     [