diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index f925b88c..f8b815a9 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -16,7 +16,7 @@ jobs:
       - name: Set up Python
         uses: actions/setup-python@83679a892e2d95755f2dac6acb0bfd1e9ac5d548 # v6.1.0
         with:
-          python-version: '3.9'
+          python-version: '3.10'
       - name: Install tox
         run: pip install tox
       - name: Run flake8
@@ -29,7 +29,7 @@ jobs:
       - name: Set up Python
         uses: actions/setup-python@83679a892e2d95755f2dac6acb0bfd1e9ac5d548 # v6.1.0
         with:
-          python-version: '3.9'
+          python-version: '3.10'
       - name: Install tox
         run: pip install tox
       - name: Run isort
@@ -42,7 +42,7 @@ jobs:
       - name: Set up Python
         uses: actions/setup-python@83679a892e2d95755f2dac6acb0bfd1e9ac5d548 # v6.1.0
         with:
-          python-version: '3.9'
+          python-version: '3.10'
       - name: Install tox
         run: pip install tox
       - name: Run mypy
@@ -52,7 +52,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: ['3.9', '3.10', '3.11', '3.12', '3.13', '3.14']
+        python-version: ['3.10', '3.11', '3.12', '3.13', '3.14']
     steps:
       - uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1
       - name: Set up Python ${{ matrix.python-version }}
@@ -78,7 +78,7 @@ jobs:
   test_nooptionals:
     runs-on: ubuntu-latest
     env:
-      PYTHON_VERSION: '3.9'
+      PYTHON_VERSION: '3.10'
     steps:
       - uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1
       - name: Set up Python
@@ -95,7 +95,7 @@ jobs:
   test_pypy:
     runs-on: ubuntu-latest
     env:
-      PYTHON_VERSION: '3.9'
+      PYTHON_VERSION: '3.10'
     steps:
       - uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1
       - name: Set up PyPy
diff --git a/pyproject.toml b/pyproject.toml
index 8b39c12d..85e1d499 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -12,7 +12,7 @@ license-files = [
 	"LICENSE",
 	"NOTICE",
 ]
-requires-python = ">=3.9"
+requires-python = ">=3.10"
 authors = [
     { name = "The Prometheus Authors", email = "prometheus-developers@googlegroups.com" },
 ]
@@ -29,7 +29,6 @@ classifiers = [
     "Intended Audience :: System Administrators",
     "Programming Language :: Python",
     "Programming Language :: Python :: 3",
-    "Programming Language :: Python :: 3.9",
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
     "Programming Language :: Python :: 3.12",
diff --git a/tox.ini b/tox.ini
index 6a006d0d..d7326324 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,5 +1,5 @@
 [tox]
-envlist = coverage-clean,py{3.9,3.10,3.11,3.12,3.13,3.14,py3.9,3.9-nooptionals},coverage-report,flake8,isort,mypy
+envlist = coverage-clean,py{3.10,3.11,3.12,3.13,3.14,py3.10,3.10-nooptionals},coverage-report,flake8,isort,mypy
 
 [testenv]
 deps =
@@ -8,14 +8,14 @@ deps =
     pytest
     pytest-benchmark
     attrs
-    {py3.9,pypy3.9}: twisted
-    {py3.9,pypy3.9}: aiohttp
-    {py3.9,pypy3.9}: django
-    {py3.9,pypy3.9}: starlette
-    {py3.9}: python-snappy
+    {py3.10,pypy3.10}: twisted
+    {py3.10,pypy3.10}: aiohttp
+    {py3.10,pypy3.10}: django
+    {py3.10,pypy3.10}: starlette
+    {py3.10}: python-snappy
 commands = coverage run --parallel -m pytest {posargs}
 
-[testenv:py3.9-nooptionals]
+[testenv:py3.10-nooptionals]
 commands = coverage run --parallel -m pytest {posargs}
 
 [testenv:coverage-clean]