diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 97d58d8ae5..da05c605ce 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -89,6 +89,25 @@ jobs:
             gh release create "${{ inputs.git-tag }}" --draft --repo "${{ github.repository }}" --title "Release ${{ inputs.git-tag }}" --notes "Release ${{ inputs.git-tag }}"
           fi
 
+  check-release-notes:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout Source
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd  # v6.0.2
+        with:
+          ref: ${{ inputs.git-tag }}
+
+      - name: Set up Python
+        uses: actions/setup-python@a26af69be951a213d495a4c3e4e4022e16d87065  # v5.6.0
+        with:
+          python-version: "3.12"
+
+      - name: Check versioned release notes exist
+        run: |
+          python toolshed/check_release_notes.py \
+            --git-tag "${{ inputs.git-tag }}" \
+            --component "${{ inputs.component }}"
+
   doc:
     name: Build release docs
     if: ${{ github.repository_owner == 'nvidia' }}
@@ -99,6 +118,7 @@ jobs:
       pull-requests: write
     needs:
       - check-tag
+      - check-release-notes
       - determine-run-id
     secrets: inherit
     uses: ./.github/workflows/build-docs.yml
@@ -114,6 +134,7 @@ jobs:
       contents: write
     needs:
       - check-tag
+      - check-release-notes
       - determine-run-id
       - doc
     secrets: inherit
@@ -128,6 +149,7 @@ jobs:
     runs-on: ubuntu-latest
     needs:
       - check-tag
+      - check-release-notes
       - determine-run-id
       - doc
     environment:
diff --git a/toolshed/check_release_notes.py b/toolshed/check_release_notes.py
new file mode 100644
index 0000000000..1b4677d67f
--- /dev/null
+++ b/toolshed/check_release_notes.py
@@ -0,0 +1,101 @@
+# SPDX-FileCopyrightText: Copyright (c) 2025-2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+"""Check that versioned release-notes files exist before releasing.
+
+Usage:
+    python check_release_notes.py --git-tag <tag> --component <component>
+
+Exit codes:
+    0 — all release notes present and non-empty (or .post version, skipped)
+    1 — one or more release notes missing or empty
+    2 — invalid arguments
+"""
+
+from __future__ import annotations
+
+import argparse
+import os
+import re
+import sys
+
+COMPONENT_TO_PACKAGES: dict[str, list[str]] = {
+    "cuda-core": ["cuda_core"],
+    "cuda-bindings": ["cuda_bindings"],
+    "cuda-pathfinder": ["cuda_pathfinder"],
+    "cuda-python": ["cuda_python"],
+    "all": ["cuda_bindings", "cuda_core", "cuda_pathfinder", "cuda_python"],
+}
+
+# Matches tags like "v13.1.0", "cuda-core-v0.7.0", "cuda-pathfinder-v1.5.2"
+TAG_RE = re.compile(r"^(?:cuda-\w+-)?v(.+)$")
+
+
+def parse_version_from_tag(git_tag: str) -> str | None:
+    """Extract the bare version string (e.g. '13.1.0') from a git tag."""
+    m = TAG_RE.match(git_tag)
+    return m.group(1) if m else None
+
+
+def is_post_release(version: str) -> bool:
+    return ".post" in version
+
+
+def notes_path(package: str, version: str) -> str:
+    return os.path.join(package, "docs", "source", "release", f"{version}-notes.rst")
+
+
+def check_release_notes(git_tag: str, component: str, repo_root: str = ".") -> list[tuple[str, str]]:
+    """Return a list of (path, reason) for missing or empty release notes.
+
+    Returns an empty list when all notes are present and non-empty.
+    """
+    version = parse_version_from_tag(git_tag)
+    if version is None:
+        return [("<tag>", f"cannot parse version from tag '{git_tag}'")]
+
+    if is_post_release(version):
+        return []
+
+    packages = COMPONENT_TO_PACKAGES.get(component)
+    if packages is None:
+        return [("<component>", f"unknown component '{component}'")]
+
+    problems = []
+    for pkg in packages:
+        path = notes_path(pkg, version)
+        full = os.path.join(repo_root, path)
+        if not os.path.isfile(full):
+            problems.append((path, "missing"))
+        elif os.path.getsize(full) == 0:
+            problems.append((path, "empty"))
+
+    return problems
+
+
+def main(argv: list[str] | None = None) -> int:
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument("--git-tag", required=True)
+    parser.add_argument("--component", required=True, choices=list(COMPONENT_TO_PACKAGES))
+    parser.add_argument("--repo-root", default=".")
+    args = parser.parse_args(argv)
+
+    version = parse_version_from_tag(args.git_tag)
+    if version and is_post_release(version):
+        print(f"Post-release tag ({args.git_tag}), skipping release-notes check.")
+        return 0
+
+    problems = check_release_notes(args.git_tag, args.component, args.repo_root)
+    if not problems:
+        print(f"Release notes present for tag {args.git_tag}, component {args.component}.")
+        return 0
+
+    print(f"ERROR: missing or empty release notes for tag {args.git_tag}:")
+    for path, reason in problems:
+        print(f"  - {path} ({reason})")
+    print("Add versioned release notes before releasing.")
+    return 1
+
+
+if __name__ == "__main__":
+    sys.exit(main())
diff --git a/toolshed/tests/test_check_release_notes.py b/toolshed/tests/test_check_release_notes.py
new file mode 100644
index 0000000000..b55de91aec
--- /dev/null
+++ b/toolshed/tests/test_check_release_notes.py
@@ -0,0 +1,116 @@
+# SPDX-FileCopyrightText: Copyright (c) 2025-2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+from __future__ import annotations
+
+import os
+import sys
+
+sys.path.insert(0, os.path.join(os.path.dirname(__file__), ".."))
+from check_release_notes import (
+    check_release_notes,
+    is_post_release,
+    main,
+    parse_version_from_tag,
+)
+
+
+class TestParseVersionFromTag:
+    def test_plain_tag(self):
+        assert parse_version_from_tag("v13.1.0") == "13.1.0"
+
+    def test_component_prefix_core(self):
+        assert parse_version_from_tag("cuda-core-v0.7.0") == "0.7.0"
+
+    def test_component_prefix_pathfinder(self):
+        assert parse_version_from_tag("cuda-pathfinder-v1.5.2") == "1.5.2"
+
+    def test_post_release(self):
+        assert parse_version_from_tag("v12.6.2.post1") == "12.6.2.post1"
+
+    def test_invalid_tag(self):
+        assert parse_version_from_tag("not-a-tag") is None
+
+    def test_no_v_prefix(self):
+        assert parse_version_from_tag("13.1.0") is None
+
+
+class TestIsPostRelease:
+    def test_normal(self):
+        assert not is_post_release("13.1.0")
+
+    def test_post(self):
+        assert is_post_release("12.6.2.post1")
+
+    def test_post_no_number(self):
+        assert is_post_release("1.0.0.post")
+
+
+class TestCheckReleaseNotes:
+    def _make_notes(self, tmp_path, pkg, version, content="Release notes."):
+        d = tmp_path / pkg / "docs" / "source" / "release"
+        d.mkdir(parents=True, exist_ok=True)
+        f = d / f"{version}-notes.rst"
+        f.write_text(content)
+        return f
+
+    def test_present_and_nonempty(self, tmp_path):
+        self._make_notes(tmp_path, "cuda_core", "0.7.0")
+        problems = check_release_notes("cuda-core-v0.7.0", "cuda-core", str(tmp_path))
+        assert problems == []
+
+    def test_missing(self, tmp_path):
+        problems = check_release_notes("cuda-core-v0.7.0", "cuda-core", str(tmp_path))
+        assert len(problems) == 1
+        assert problems[0][1] == "missing"
+
+    def test_empty(self, tmp_path):
+        self._make_notes(tmp_path, "cuda_core", "0.7.0", content="")
+        problems = check_release_notes("cuda-core-v0.7.0", "cuda-core", str(tmp_path))
+        assert len(problems) == 1
+        assert problems[0][1] == "empty"
+
+    def test_post_release_skipped(self, tmp_path):
+        problems = check_release_notes("v12.6.2.post1", "cuda-bindings", str(tmp_path))
+        assert problems == []
+
+    def test_component_all(self, tmp_path):
+        for pkg in ("cuda_bindings", "cuda_core", "cuda_pathfinder", "cuda_python"):
+            self._make_notes(tmp_path, pkg, "13.1.0")
+        problems = check_release_notes("v13.1.0", "all", str(tmp_path))
+        assert problems == []
+
+    def test_component_all_partial_missing(self, tmp_path):
+        self._make_notes(tmp_path, "cuda_bindings", "13.1.0")
+        self._make_notes(tmp_path, "cuda_core", "13.1.0")
+        problems = check_release_notes("v13.1.0", "all", str(tmp_path))
+        assert len(problems) == 2
+        missing_pkgs = {p.split("/")[0] for p, _ in problems}
+        assert missing_pkgs == {"cuda_pathfinder", "cuda_python"}
+
+    def test_invalid_tag(self, tmp_path):
+        problems = check_release_notes("not-a-tag", "cuda-core", str(tmp_path))
+        assert len(problems) == 1
+        assert "cannot parse" in problems[0][1]
+
+    def test_plain_v_tag(self, tmp_path):
+        self._make_notes(tmp_path, "cuda_python", "13.1.0")
+        problems = check_release_notes("v13.1.0", "cuda-python", str(tmp_path))
+        assert problems == []
+
+
+class TestMain:
+    def test_success(self, tmp_path):
+        d = tmp_path / "cuda_core" / "docs" / "source" / "release"
+        d.mkdir(parents=True)
+        (d / "0.7.0-notes.rst").write_text("Notes here.")
+        rc = main(["--git-tag", "cuda-core-v0.7.0", "--component", "cuda-core", "--repo-root", str(tmp_path)])
+        assert rc == 0
+
+    def test_failure(self, tmp_path):
+        rc = main(["--git-tag", "cuda-core-v0.7.0", "--component", "cuda-core", "--repo-root", str(tmp_path)])
+        assert rc == 1
+
+    def test_post_skip(self, tmp_path):
+        rc = main(["--git-tag", "v12.6.2.post1", "--component", "cuda-bindings", "--repo-root", str(tmp_path)])
+        assert rc == 0