diff --git a/flit/upload.py b/flit/upload.py
index 15a7334a..162a18c4 100644
--- a/flit/upload.py
+++ b/flit/upload.py
@@ -254,7 +254,7 @@ def do_upload(file:Path, metadata:Metadata, pypirc_path="~/.pypirc", repo_name=N
         log.info("Package is at %s/%s", repo['url'], metadata.name)
 
 
-def main(ini_path, repo_name, pypirc_path, formats=None, gen_setup_py=True):
+def main(ini_path, repo_name, pypirc_path=None, formats=None, gen_setup_py=True):
     """Build and upload wheel and sdist."""
     if pypirc_path is None:
         pypirc_path = PYPIRC_DEFAULT
diff --git a/tests/test_upload.py b/tests/test_upload.py
index 740602df..cef98795 100644
--- a/tests/test_upload.py
+++ b/tests/test_upload.py
@@ -155,3 +155,16 @@ def test_upload_invalid_pypirc_file(copy_sample):
                 repo_name="test123",
                 pypirc_path="./file.invalid",
             )
+
+def test_upload_default_pypirc_file(copy_sample):
+    with patch("flit.upload.do_upload") as do_upload:
+        td = copy_sample("module1_toml")
+        formats = list(ALL_FORMATS)[:1]
+        upload.main(
+            td / "pyproject.toml",
+            formats=set(formats),
+            repo_name="test123",
+        )
+
+        file = do_upload.call_args[0][2]
+        assert file == "~/.pypirc"