diff --git a/pyproject.toml b/pyproject.toml
index ee30835..b2957b9 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -82,11 +82,6 @@ strict_equality = true
 warn_unreachable = true
 warn_no_return = true
 
-[[tool.mypy.overrides]]
-module = "tests.*"
-disallow_incomplete_defs = false
-disallow_untyped_defs = false
-
 
 # Pytest
 # ======
diff --git a/tests/sort_lines_test.py b/tests/sort_lines_test.py
index 7e66c2b..f68013d 100644
--- a/tests/sort_lines_test.py
+++ b/tests/sort_lines_test.py
@@ -68,7 +68,7 @@ def test_unknown_options(self) -> None:
 
 
 class TestSortLines:
-    def test_sort_lines(self):
+    def test_sort_lines(self) -> None:
         lines = [
             '# pragma: alphabetize\n',
             'Bob\n',
@@ -89,7 +89,7 @@ def test_sort_lines(self):
             'Eve\n',
         ]
 
-    def test_case_insensitive(self):
+    def test_case_insensitive(self) -> None:
         lines = [
             '# pragma: alphabetize[case-insensitive]\n',
             'Bob\n',
@@ -110,7 +110,7 @@ def test_case_insensitive(self):
             'eve\n',
         ]
 
-    def test_already_sorted(self):
+    def test_already_sorted(self) -> None:
         lines = [
             '# pragma: alphabetize\n',
             'Alice\n',
@@ -124,7 +124,7 @@ def test_already_sorted(self):
 
         assert sorted_lines == lines
 
-    def test_sorting_stops_when_indentation_changes(self):
+    def test_sorting_stops_when_indentation_changes(self) -> None:
         lines = [
             '# pragma: alphabetize\n',
             '    Bob\n',
@@ -145,7 +145,7 @@ def test_sorting_stops_when_indentation_changes(self):
             'Charlie\n',
         ]
 
-    def test_sorting_stops_at_empty_line(self):
+    def test_sorting_stops_at_empty_line(self) -> None:
         lines = [
             '# pragma: alphabetize\n',
             'Bob\n',
@@ -169,7 +169,7 @@ def test_sorting_stops_at_empty_line(self):
         ]
 
 
-def test_file_needs_no_sorting(tmp_path: Path):
+def test_file_needs_no_sorting(tmp_path: Path) -> None:
     file = tmp_path / 't.py'
     file.write_text(
         """\
@@ -195,7 +195,7 @@ def test_file_needs_no_sorting(tmp_path: Path):
 """
 
 
-def test_file_already_sorted(tmp_path: Path):
+def test_file_already_sorted(tmp_path: Path) -> None:
     file = tmp_path / 't.py'
     file.write_text(
         """\
@@ -239,7 +239,7 @@ def test_file_already_sorted(tmp_path: Path):
 """
 
 
-def test_file_changed(tmp_path: Path):
+def test_file_changed(tmp_path: Path) -> None:
     file = tmp_path / 't.py'
     file.write_text(
         """\
@@ -347,7 +347,7 @@ def test_file_changed(tmp_path: Path):
 """
 
 
-def test_case_insensitive(tmp_path: Path):
+def test_case_insensitive(tmp_path: Path) -> None:
     file = tmp_path / 't.py'
     file.write_text(
         """\
@@ -455,7 +455,7 @@ def test_case_insensitive(tmp_path: Path):
 """
 
 
-def test_multiple_files(tmp_path: Path):
+def test_multiple_files(tmp_path: Path) -> None:
     unchanged_file = tmp_path / 'unchanged.py'
     unchanged_file.write_text(
         """\