diff --git a/.github/workflows/python.yml b/.github/workflows/python.yml
index bca37060..db972b25 100644
--- a/.github/workflows/python.yml
+++ b/.github/workflows/python.yml
@@ -26,7 +26,7 @@ jobs:
     - name: Set up Python
       uses: actions/setup-python@v7
       with:
-        python-version: '3.14'
+        python-version: '3.15'
     - name: Install dependencies
       run: python -m pip install prek uv
     - name: Cache pre-commit environments
@@ -50,11 +50,11 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest, ubuntu-24.04-arm, macos-latest]
-        python-version: ["3.10", "3.11", "3.12", "3.13", "3.13t", "3.14", "3.14t"]
+        python-version: ["3.10", "3.11", "3.12", "3.13", "3.13t", "3.14", "3.14t", "3.15", "3.15t"]
         openslide: [system, wheel]
         include:
           - os: ubuntu-latest
-            python-version: "3.14"
+            python-version: "3.15"
             openslide: system
             sdist: sdist
     steps:
@@ -169,7 +169,7 @@ jobs:
         shell: bash
     strategy:
       matrix:
-        python-version: ["3.10", "3.11", "3.12", "3.13", "3.13t", "3.14", "3.14t"]
+        python-version: ["3.10", "3.11", "3.12", "3.13", "3.13t", "3.14", "3.14t", "3.15", "3.15t"]
         openslide: [zip, wheel]
     steps:
     - name: Check out repo
@@ -267,7 +267,7 @@ jobs:
     - name: Set up Python
       uses: actions/setup-python@v7
       with:
-        python-version: '3.14'
+        python-version: '3.15'
     - name: Install Python tools
       run: |
         python -m pip install --upgrade pip
diff --git a/pyproject.toml b/pyproject.toml
index c53416e9..532231ff 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -23,6 +23,7 @@ classifiers = [
     "Programming Language :: Python :: 3.12",
     "Programming Language :: Python :: 3.13",
     "Programming Language :: Python :: 3.14",
+    "Programming Language :: Python :: 3.15",
     "Programming Language :: Python :: Free Threading :: 2 - Beta",
     "Topic :: Scientific/Engineering :: Bio-Informatics",
     "Typing :: Typed",