diff --git a/src/flake8/options/config.py b/src/flake8/options/config.py
index 7cba936..9756e7d 100644
--- a/src/flake8/options/config.py
+++ b/src/flake8/options/config.py
@@ -20,7 +20,7 @@ def _find_config_file(path: str) -> Optional[str]:
         for candidate in ("setup.cfg", "tox.ini", ".flake8"):
             cfg_path = os.path.join(path, candidate)
             try:
-                cfg.read(cfg_path)
+                cfg.read(cfg_path, encoding="UTF-8")
             except (UnicodeDecodeError, configparser.ParsingError) as e:
                 LOG.warning("ignoring unparseable config %s: %s", cfg_path, e)
             else:
@@ -61,7 +61,7 @@ def load_config(
 
     cfg = configparser.RawConfigParser()
     if config is not None:
-        if not cfg.read(config):
+        if not cfg.read(config, encoding="UTF-8"):
             raise exceptions.ExecutionError(
                 f"The specified config file does not exist: {config}"
             )
@@ -72,7 +72,7 @@ def load_config(
     # TODO: remove this and replace it with configuration modifying plugins
     # read the additional configs afterwards
     for filename in extra:
-        cfg.read(filename)
+        cfg.read(filename, encoding="UTF-8")
 
     return cfg, cfg_dir
 
diff --git a/tests/unit/test_options_config.py b/tests/unit/test_options_config.py
index c5d1476..02dd218 100644
--- a/tests/unit/test_options_config.py
+++ b/tests/unit/test_options_config.py
@@ -118,6 +118,31 @@ def test_load_config_append_config(tmpdir):
     assert cfg_dir == str(tmpdir)
 
 
+NON_ASCII_CONFIG = "# ☃\n[flake8]\nindent-size=8\n"
+
+
+def test_load_auto_config_utf8(tmpdir):
+    tmpdir.join("setup.cfg").write_text(NON_ASCII_CONFIG, encoding="UTF-8")
+    with tmpdir.as_cwd():
+        cfg, cfg_dir = config.load_config(None, [], isolated=False)
+    assert cfg["flake8"]["indent-size"] == "8"
+
+
+def test_load_explicit_config_utf8(tmpdir):
+    tmpdir.join("t.cfg").write_text(NON_ASCII_CONFIG, encoding="UTF-8")
+    with tmpdir.as_cwd():
+        cfg, cfg_dir = config.load_config("t.cfg", [], isolated=False)
+    assert cfg["flake8"]["indent-size"] == "8"
+
+
+def test_load_extra_config_utf8(tmpdir):
+    tmpdir.join("setup.cfg").write("[flake8]\nindent-size=2\n")
+    tmpdir.join("t.cfg").write_text(NON_ASCII_CONFIG, encoding="UTF-8")
+    with tmpdir.as_cwd():
+        cfg, cfg_dir = config.load_config(None, ["t.cfg"], isolated=False)
+    assert cfg["flake8"]["indent-size"] == "8"
+
+
 @pytest.fixture
 def opt_manager():
     ret = OptionManager(version="123", plugin_versions="", parents=[])