diff --git a/.github/workflows/pull-request.yaml b/.github/workflows/pull-request.yaml
index e2353f89..053ca40e 100644
--- a/.github/workflows/pull-request.yaml
+++ b/.github/workflows/pull-request.yaml
@@ -69,10 +69,10 @@ jobs:
         run: uv run pytest tests/integration/test_py.py tests/error/test_py_errors.py tests/integration/test_tket.py
 
   test-coverage:
-    name: Check Python (3.12) with coverage
+    name: Check Python (3.13) with coverage
     runs-on: ubuntu-latest
     env:
-      PYTHON_VERSION: '3.12'
+      PYTHON_VERSION: '3.13'
 
     steps:
       - uses: actions/checkout@v4
diff --git a/execute_llvm/pyproject.toml b/execute_llvm/pyproject.toml
index fa102eda..57f297b6 100644
--- a/execute_llvm/pyproject.toml
+++ b/execute_llvm/pyproject.toml
@@ -1,6 +1,6 @@
 [project]
 name = "execute-llvm"
-requires-python = ">=3.10,<3.13"
+requires-python = ">=3.10,<4"
 classifiers = [
     "Private :: Do Not Upload",
     "Programming Language :: Rust",
diff --git a/pyproject.toml b/pyproject.toml
index 82e577c8..8736dfa1 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,7 +1,7 @@
 [project]
 name = "guppylang"
 version = "0.12.1"
-requires-python = ">=3.10,<3.13"
+requires-python = ">=3.10,<4"
 description = "Pythonic quantum-classical programming language"
 license = { file = "LICENCE" }
 readme = "quickstart.md"
diff --git a/uv.lock b/uv.lock
index d415f199..64920518 100644
--- a/uv.lock
+++ b/uv.lock
@@ -1,5 +1,9 @@
 version = 1
-requires-python = ">=3.10, <3.13"
+requires-python = ">=3.10, <4"
+resolution-markers = [
+    "python_full_version < '3.13'",
+    "python_full_version >= '3.13'",
+]
 
 [manifest]
 members = [