diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index eacd67c6..9d630de6 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -12,12 +12,12 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.8", "3.9", "3.10", "3.11", "3.12-dev", "pypy-3.9"]
+        python-version: ["3.9", "3.10", "3.11", "3.12", "3.13", "pypy-3.9"]
         os: [ubuntu-latest]
         # Include minimum py3 + maximum py3 + pypy3 on Windows
         include:
-          - { os: "windows-latest" , python-version: "3.8" }
-          - { os: "windows-latest" , python-version: "3.11" }
+          - { os: "windows-latest" , python-version: "3.9" }
+          - { os: "windows-latest" , python-version: "3.13" }
           - { os: "windows-latest" , python-version: "pypy-3.9" }
 
     steps:
diff --git a/pyflakes/test/test_api.py b/pyflakes/test/test_api.py
index ec1cbdbf..41201e4e 100644
--- a/pyflakes/test/test_api.py
+++ b/pyflakes/test/test_api.py
@@ -479,16 +479,12 @@ def foo(bar=baz, bax):
             else:
                 msg = 'non-default argument follows default argument'
 
-            if PYPY and sys.version_info >= (3, 9):
+            if PYPY:
                 column = 18
-            elif PYPY:
-                column = 8
             elif sys.version_info >= (3, 10):
                 column = 18
-            elif sys.version_info >= (3, 9):
-                column = 21
             else:
-                column = 9
+                column = 21
             last_line = ' ' * (column - 1) + '^\n'
             self.assertHasErrors(
                 sourcePath,
@@ -508,23 +504,13 @@ def test_nonKeywordAfterKeywordSyntaxError(self):
 foo(bar=baz, bax)
 """
         with self.makeTempFile(source) as sourcePath:
-            if sys.version_info >= (3, 9):
-                column = 17
-            elif not PYPY:
-                column = 14
-            else:
-                column = 13
-            last_line = ' ' * (column - 1) + '^\n'
-            columnstr = '%d:' % column
-
-            message = 'positional argument follows keyword argument'
-
+            last_line = ' ' * 16 + '^\n'
             self.assertHasErrors(
                 sourcePath,
-                ["""\
-{}:1:{} {}
+                [f"""\
+{sourcePath}:1:17: positional argument follows keyword argument
 foo(bar=baz, bax)
-{}""".format(sourcePath, columnstr, message, last_line)])
+{last_line}"""])
 
     def test_invalidEscape(self):
         """
@@ -533,11 +519,9 @@ def test_invalidEscape(self):
         # ValueError: invalid \x escape
         with self.makeTempFile(r"foo = '\xyz'") as sourcePath:
             position_end = 1
-            if PYPY and sys.version_info >= (3, 9):
+            if PYPY:
                 column = 7
-            elif PYPY:
-                column = 6
-            elif (3, 9) <= sys.version_info < (3, 12):
+            elif sys.version_info < (3, 12):
                 column = 13
             else:
                 column = 7
@@ -669,23 +653,11 @@ def test_stdinReportsErrors(self):
         self.assertEqual(count, 1)
         errlines = err.getvalue().split("\n")[:-1]
 
-        if sys.version_info >= (3, 9):
-            expected_error = [
-                "<stdin>:1:5: Generator expression must be parenthesized",
-                "max(1 for i in range(10), key=lambda x: x+1)",
-                "    ^",
-            ]
-        elif PYPY:
-            expected_error = [
-                "<stdin>:1:4: Generator expression must be parenthesized if not sole argument",  # noqa: E501
-                "max(1 for i in range(10), key=lambda x: x+1)",
-                "   ^",
-            ]
-        else:
-            expected_error = [
-                "<stdin>:1:5: Generator expression must be parenthesized",
-            ]
-
+        expected_error = [
+            "<stdin>:1:5: Generator expression must be parenthesized",
+            "max(1 for i in range(10), key=lambda x: x+1)",
+            "    ^",
+        ]
         self.assertEqual(errlines, expected_error)
 
 
@@ -774,8 +746,14 @@ def test_errors_syntax(self):
         with open(self.tempfilepath, 'wb') as fd:
             fd.write(b"import")
         d = self.runPyflakes([self.tempfilepath])
-        error_msg = '{0}:1:7: invalid syntax{1}import{1}      ^{1}'.format(
-            self.tempfilepath, os.linesep)
+
+        if sys.version_info >= (3, 13):
+            message = "Expected one or more names after 'import'"
+        else:
+            message = 'invalid syntax'
+
+        error_msg = '{0}:1:7: {1}{2}import{2}      ^{2}'.format(
+            self.tempfilepath, message, os.linesep)
         self.assertEqual(d, ('', error_msg, 1))
 
     def test_readFromStdin(self):
diff --git a/pyflakes/test/test_type_annotations.py b/pyflakes/test/test_type_annotations.py
index 4c8b998f..343083e7 100644
--- a/pyflakes/test/test_type_annotations.py
+++ b/pyflakes/test/test_type_annotations.py
@@ -797,3 +797,10 @@ def g(*args: P.args, **kwargs: P.kwargs) -> R:
                 return f(*args, **kwargs)
             return g
         """)
+
+    @skipIf(version_info < (3, 13), 'new in Python 3.13')
+    def test_type_parameter_defaults(self):
+        self.flakes("""
+        def f[T = int](u: T) -> T:
+            return u
+        """)
diff --git a/setup.py b/setup.py
index 3cc2fbd9..437353fd 100755
--- a/setup.py
+++ b/setup.py
@@ -42,7 +42,7 @@ def get_long_description():
     author_email="code-quality@python.org",
     url="https://github.com/PyCQA/pyflakes",
     packages=["pyflakes", "pyflakes.scripts", "pyflakes.test"],
-    python_requires='>=3.8',
+    python_requires='>=3.9',
     classifiers=[
         "Development Status :: 6 - Mature",
         "Environment :: Console",