diff --git a/py-polars/polars/io/csv/functions.py b/py-polars/polars/io/csv/functions.py
index daebcf452c1e..0483d058180b 100644
--- a/py-polars/polars/io/csv/functions.py
+++ b/py-polars/polars/io/csv/functions.py
@@ -1036,7 +1036,7 @@ def scan_csv(
     decimal_comma: bool = False,
     glob: bool = True,
     storage_options: dict[str, Any] | None = None,
-    credential_provider: CredentialProviderFunction | Literal["auto"] | None = None,
+    credential_provider: CredentialProviderFunction | Literal["auto"] | None = "auto",
     retries: int = 2,
     file_cache_ttl: int | None = None,
     include_file_paths: str | None = None,
diff --git a/py-polars/polars/io/ipc/functions.py b/py-polars/polars/io/ipc/functions.py
index 1348134fc0d6..b8af12ae8806 100644
--- a/py-polars/polars/io/ipc/functions.py
+++ b/py-polars/polars/io/ipc/functions.py
@@ -364,7 +364,7 @@ def scan_ipc(
     row_index_name: str | None = None,
     row_index_offset: int = 0,
     storage_options: dict[str, Any] | None = None,
-    credential_provider: CredentialProviderFunction | Literal["auto"] | None = None,
+    credential_provider: CredentialProviderFunction | Literal["auto"] | None = "auto",
     memory_map: bool = True,
     retries: int = 2,
     file_cache_ttl: int | None = None,
diff --git a/py-polars/polars/io/ndjson.py b/py-polars/polars/io/ndjson.py
index 983b8cddcfe1..7da4635408d1 100644
--- a/py-polars/polars/io/ndjson.py
+++ b/py-polars/polars/io/ndjson.py
@@ -38,7 +38,7 @@ def read_ndjson(
     row_index_offset: int = 0,
     ignore_errors: bool = False,
     storage_options: dict[str, Any] | None = None,
-    credential_provider: CredentialProviderFunction | Literal["auto"] | None = None,
+    credential_provider: CredentialProviderFunction | Literal["auto"] | None = "auto",
     retries: int = 2,
     file_cache_ttl: int | None = None,
     include_file_paths: str | None = None,
@@ -206,7 +206,7 @@ def scan_ndjson(
     row_index_offset: int = 0,
     ignore_errors: bool = False,
     storage_options: dict[str, Any] | None = None,
-    credential_provider: CredentialProviderFunction | Literal["auto"] | None = None,
+    credential_provider: CredentialProviderFunction | Literal["auto"] | None = "auto",
     retries: int = 2,
     file_cache_ttl: int | None = None,
     include_file_paths: str | None = None,
diff --git a/py-polars/polars/io/parquet/functions.py b/py-polars/polars/io/parquet/functions.py
index 16ff7f614349..0cc91a94693f 100644
--- a/py-polars/polars/io/parquet/functions.py
+++ b/py-polars/polars/io/parquet/functions.py
@@ -54,7 +54,7 @@ def read_parquet(
     rechunk: bool = False,
     low_memory: bool = False,
     storage_options: dict[str, Any] | None = None,
-    credential_provider: CredentialProviderFunction | Literal["auto"] | None = None,
+    credential_provider: CredentialProviderFunction | Literal["auto"] | None = "auto",
     retries: int = 2,
     use_pyarrow: bool = False,
     pyarrow_options: dict[str, Any] | None = None,
@@ -338,7 +338,7 @@ def scan_parquet(
     low_memory: bool = False,
     cache: bool = True,
     storage_options: dict[str, Any] | None = None,
-    credential_provider: CredentialProviderFunction | Literal["auto"] | None = None,
+    credential_provider: CredentialProviderFunction | Literal["auto"] | None = "auto",
     retries: int = 2,
     include_file_paths: str | None = None,
     allow_missing_columns: bool = False,
diff --git a/py-polars/tests/unit/io/cloud/test_cloud.py b/py-polars/tests/unit/io/cloud/test_cloud.py
index f943ab5e2c26..54d1b5ccd6a6 100644
--- a/py-polars/tests/unit/io/cloud/test_cloud.py
+++ b/py-polars/tests/unit/io/cloud/test_cloud.py
@@ -1,3 +1,5 @@
+from functools import partial
+
 import pytest
 
 import polars as pl
@@ -11,6 +13,11 @@ def test_scan_nonexistent_cloud_path_17444(format: str) -> None:
 
     path_str = f"s3://my-nonexistent-bucket/data.{format}"
     scan_function = getattr(pl, f"scan_{format}")
+    # Prevent automatic credential provideder instantiation, otherwise CI may fail with
+    # * pytest.PytestUnraisableExceptionWarning:
+    #   * Exception ignored:
+    #     * ResourceWarning: unclosed socket
+    scan_function = partial(scan_function, credential_provider=None)
 
     # Just calling the scan function should not raise any errors
     if format == "ndjson":