diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 73ab5e0..2bfa036 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -22,8 +22,6 @@ jobs:
       fail-fast: false
       matrix:
         python-version:
-        - "3.9"
-        - "3.10"
         - "3.11"
         - "3.12"
         - "3.13"
diff --git a/.ruff.toml b/.ruff.toml
index e60e99e..7c3340e 100644
--- a/.ruff.toml
+++ b/.ruff.toml
@@ -1,4 +1,4 @@
-target-version = "py39"  # Pin Ruff to Python 3.9
+target-version = "py311"  # Pin Ruff to Python 3.11
 line-length = 88
 output-format = "full"
 extend-exclude = [
@@ -15,6 +15,7 @@ ignore = [
     "D105",
     "D107",
     "E203",
+    "UP038", # This rule is deprecated and will be removed in a future release.
 #    "W503", # unimplemented in Ruff (as of 2024-04-16)
 ]
 select = [
diff --git a/CONTRIBUTING.rst b/CONTRIBUTING.rst
index e1f1d84..a102530 100644
--- a/CONTRIBUTING.rst
+++ b/CONTRIBUTING.rst
@@ -27,7 +27,7 @@ Set-up
 
        $ git clone https://github.com/YOUR_USERNAME_HERE/sphinx-autobuild
 
-To work on this project, you need Python 3.9 or newer.
+To work on this project, you need Python 3.11 or newer.
 Most of this project's development workflow commands use nox_.
 
 If you're not sure how to install nox,
diff --git a/NEWS.rst b/NEWS.rst
index a8d4f18..c9e9bf8 100644
--- a/NEWS.rst
+++ b/NEWS.rst
@@ -4,6 +4,8 @@ Changelog
 unreleased
 ----------
 
+* Drop support for Python 3.9-3.10 to match Sphinx.
+
 2024.10.03 - 2024-10-03
 -----------------------
 
diff --git a/noxfile.py b/noxfile.py
index 0be1500..5c24a7d 100644
--- a/noxfile.py
+++ b/noxfile.py
@@ -9,7 +9,7 @@ def lint(session):
     session.run("pre-commit", "run", "--all-files", *session.posargs)
 
 
-@nox.session(python=["3.9", "3.10", "3.11", "3.12", "3.13"])
+@nox.session(python=["3.11", "3.12", "3.13"])
 def test(session):
     session.install("-e", ".[test]", silent=True)
     session.run("pytest", *session.posargs)
diff --git a/pyproject.toml b/pyproject.toml
index 9e7b733..c95a7c1 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -13,7 +13,7 @@ authors = [
   { name = "Adam Turner" },
   { name = "Jonathan Stoppani", email = "jonathan@stoppani.name" },
 ]
-requires-python = ">=3.9"
+requires-python = ">=3.11"
 classifiers = [
   "Development Status :: 5 - Production/Stable",
   "Environment :: Console",
@@ -24,8 +24,6 @@ classifiers = [
   "Operating System :: OS Independent",
   "Programming Language :: Python",
   "Programming Language :: Python :: 3 :: Only",
-  "Programming Language :: Python :: 3.9",
-  "Programming Language :: Python :: 3.10",
   "Programming Language :: Python :: 3.11",
   "Programming Language :: Python :: 3.12",
   "Programming Language :: Python :: 3.13",