diff --git a/cibuildwheel/macos.py b/cibuildwheel/macos.py
index 6e895836..69a06c04 100644
--- a/cibuildwheel/macos.py
+++ b/cibuildwheel/macos.py
@@ -194,7 +194,9 @@ def build(options: BuildOptions) -> None:
         if os.path.exists(built_wheel_dir):
             shutil.rmtree(built_wheel_dir)
         os.makedirs(built_wheel_dir)
-        call(['pip', 'wheel', options.package_dir, '-w', built_wheel_dir, '--no-deps'] + get_build_verbosity_extra_flags(options.build_verbosity), env=env)
+        # os.path.abspath is need. Without it pip wheel may try to fetch package from pypi.org
+        # see https://github.com/joerick/cibuildwheel/pull/369
+        call(['pip', 'wheel', os.path.abspath(options.package_dir), '-w', built_wheel_dir, '--no-deps'] + get_build_verbosity_extra_flags(options.build_verbosity), env=env)
         built_wheel = glob(os.path.join(built_wheel_dir, '*.whl'))[0]
 
         # repair the wheel
diff --git a/cibuildwheel/windows.py b/cibuildwheel/windows.py
index da31b1af..c625b39a 100644
--- a/cibuildwheel/windows.py
+++ b/cibuildwheel/windows.py
@@ -180,7 +180,9 @@ def build(options: BuildOptions) -> None:
         if os.path.exists(built_wheel_dir):
             shutil.rmtree(built_wheel_dir)
         os.makedirs(built_wheel_dir)
-        shell(['pip', 'wheel', options.package_dir, '-w', built_wheel_dir, '--no-deps'] + get_build_verbosity_extra_flags(options.build_verbosity), env=env)
+        # os.path.abspath is need. Without it pip wheel may try to fetch package from pypi.org
+        # see https://github.com/joerick/cibuildwheel/pull/369
+        shell(['pip', 'wheel', os.path.abspath(options.package_dir), '-w', built_wheel_dir, '--no-deps'] + get_build_verbosity_extra_flags(options.build_verbosity), env=env)
         built_wheel = glob(os.path.join(built_wheel_dir, '*.whl'))[0]
 
         # repair the wheel
diff --git a/test/test_subdir_package.py b/test/test_subdir_package.py
index 53bd9520..98b1b8cd 100644
--- a/test/test_subdir_package.py
+++ b/test/test_subdir_package.py
@@ -35,7 +35,7 @@ def test(capfd, tmp_path):
     project_dir = tmp_path / 'project'
     subdir_package_project.generate(project_dir)
 
-    package_dir = os.path.join(project_dir, 'src', 'spam')
+    package_dir = os.path.join('src', 'spam')
     # build the wheels
     actual_wheels = utils.cibuildwheel_run(project_dir, package_dir=package_dir, add_env={
         'CIBW_BEFORE_BUILD': 'python {project}/bin/before_build.py',