diff --git a/CHANGELOG.md b/CHANGELOG.md
index 10f86b43f1..f7bf28a5e9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -43,6 +43,7 @@
 * Add `bgcolor` to `FletTestApp.take_page_controls_screenshot()`, `assert_control_screenshot()` and `wrap_page_controls_in_screenshot()` to paint an opaque background behind the captured controls instead of a transparent one ([#6918](https://github.com/flet-dev/flet/pull/6918)) by @InesaFitsner.
 * Add `--log-format {rich,plain,github}` (`FLET_CLI_LOG_FORMAT`) to `flet build`, `flet debug` and `flet test`. `github` prints plain output plus GitHub Actions workflow commands: a collapsible group per build step and annotations for warnings and errors; `plain` is the same as `--no-rich-output`. See [Log formats](/docs/cli/flet-build#log-formats) ([#6947](https://github.com/flet-dev/flet/issues/6947)) by @FeodorFitsner.
 * Install `uvicorn[standard]` with `flet-web` again on Windows on ARM with Python 3.12 or later, now that `httptools` 0.9.0 ships wheels for it; Python 3.10 and 3.11 there keep plain `uvicorn`, because PyYAML has no wheels for them ([#6927](https://github.com/flet-dev/flet/pull/6927)) by @ndonkoHenri.
+* Update python-build to `20261016` and serious_python to `6.0.0`, bringing CPython `3.12.15`, `3.13.16` and `3.14.8`. The bundled Python runtime, its native modules and dart_bridge `1.11.0` are now built for iOS 15 and macOS 12, the same minimums as the build template ([#6940](https://github.com/flet-dev/flet/issues/6940), [python-build#46](https://github.com/flet-dev/python-build/pull/46), [serious-python#256](https://github.com/flet-dev/serious-python/pull/256)) by @FeodorFitsner.
 
 ### Bug fixes
 
diff --git a/sdk/python/packages/flet-cli/src/flet_cli/utils/python_versions.py b/sdk/python/packages/flet-cli/src/flet_cli/utils/python_versions.py
index d1d8064abc..37d8c19e33 100644
--- a/sdk/python/packages/flet-cli/src/flet_cli/utils/python_versions.py
+++ b/sdk/python/packages/flet-cli/src/flet_cli/utils/python_versions.py
@@ -28,7 +28,7 @@
 # python-build release this flet pins. Keep in sync with serious_python's
 # `pythonReleaseDate` (lib/src/python_versions.dart) — both should track the
 # same python-build release.
-PYTHON_BUILD_RELEASE_DATE = "20260921"
+PYTHON_BUILD_RELEASE_DATE = "20261016"
 
 RELEASE_DATE_ENV = "FLET_PYTHON_BUILD_RELEASE_DATE"
 MANIFEST_PATH_ENV = "FLET_PYTHON_BUILD_MANIFEST"
diff --git a/sdk/python/packages/flet-web/src/flet_web/patch_index.py b/sdk/python/packages/flet-web/src/flet_web/patch_index.py
index 978e018cca..1d9d16eeb2 100644
--- a/sdk/python/packages/flet-web/src/flet_web/patch_index.py
+++ b/sdk/python/packages/flet-web/src/flet_web/patch_index.py
@@ -85,7 +85,7 @@ def patch_index_html(
     # loads it via dynamic `import()`. We can no longer use `.js` because
     # Pyodide >= 0.29 throws "Classic web workers are not supported" inside
     # any worker that has `importScripts` available — only classic workers
-    # have it. All supported Pyodide versions (0.27.7 / 0.29.4 / 314.0.6)
+    # have it. All supported Pyodide versions (0.27.8 / 0.29.5 / 314.0.7)
     # ship `pyodide.mjs`.
     if pyodide_version:
         if no_cdn:
diff --git a/sdk/python/templates/build/{{cookiecutter.out_dir}}/pubspec.yaml b/sdk/python/templates/build/{{cookiecutter.out_dir}}/pubspec.yaml
index bfcc7855c6..6a046ee29c 100644
--- a/sdk/python/templates/build/{{cookiecutter.out_dir}}/pubspec.yaml
+++ b/sdk/python/templates/build/{{cookiecutter.out_dir}}/pubspec.yaml
@@ -23,7 +23,7 @@ dependencies:
   flet:
     path: ../../../../../packages/flet
 
-  serious_python: 5.0.0
+  serious_python: 6.0.0
 
   # MsgPack codec used by the dart_bridge FletBackendChannel implementation
   # in lib/main.dart — matches the wire format flet's existing socket
diff --git a/website/docs/updates/breaking-changes/v1-1-0/minimum-macos-12-ios-15.md b/website/docs/updates/breaking-changes/v1-1-0/minimum-macos-12-ios-15.md
index 2cdd373128..bebec11474 100644
--- a/website/docs/updates/breaking-changes/v1-1-0/minimum-macos-12-ios-15.md
+++ b/website/docs/updates/breaking-changes/v1-1-0/minimum-macos-12-ios-15.md
@@ -37,7 +37,9 @@ The macOS deployment target 'MACOSX_DEPLOYMENT_TARGET' is set to 11.0, but the r
 
 Flet 1.1.0 builds with Flutter 3.47, whose engine requires these minimums, and
 raises the deployment targets in the build template and the desktop client to
-match.
+match. The embedded Python runtime, its native modules and the Dart-Python bridge
+that `flet build` bundles (from serious_python 6.0.0) are built for the same
+minimums ([#6940](https://github.com/flet-dev/flet/issues/6940)).
 
 ## Who is affected
 
@@ -109,7 +111,8 @@ accepts iOS apps built with the iOS 27 SDK, which comes with Xcode 27
 
 - Docs: [Minimum macOS version](../../../publish/macos.md#minimum-macos-version),
   [Minimum iOS version](../../../publish/ios.md#minimum-ios-version)
-- Issue: [#6874](https://github.com/flet-dev/flet/issues/6874)
+- Issues: [#6874](https://github.com/flet-dev/flet/issues/6874),
+  [#6940](https://github.com/flet-dev/flet/issues/6940)
 - Pull request: [#6914](https://github.com/flet-dev/flet/pull/6914)
 - [Flutter supported platforms](https://docs.flutter.dev/reference/supported-platforms)
 - Release notes: [Flet 1.1.0](../../release-notes.md)