diff --git a/README.md b/README.md
index de51404..ccc8d12 100644
--- a/README.md
+++ b/README.md
@@ -9,7 +9,9 @@ The Owner API will [stop working](https://developer.tesla.com/docs/fleet-api#202
 
 ## Overview
 
-This module depends on Python [requests](https://pypi.org/project/requests/), [requests_oauthlib](https://pypi.org/project/requests-oauthlib/) and [websocket-client](https://pypi.org/project/websocket-client/). It requires Python 3.10+ when using urllib3 2.0, which comes with requests 2.30.0+, or you can pin urllib3 to 1.26.x by installing `urllib3<2`.
+This module depends on Python [requests](https://pypi.org/project/requests/), [requests_oauthlib](https://pypi.org/project/requests-oauthlib/), [httpx](https://pypi.org/project/httpx/) and [websocket-client](https://pypi.org/project/websocket-client/). It requires Python 3.10+ when using urllib3 2.0, which comes with requests 2.30.0+, or you can pin urllib3 to 1.26.x by installing `urllib3<2`.
+
+As of June 2026, Tesla requires HTTP/2 for its SSO (auth.tesla.com) and Owner API endpoints; requests, which only speaks HTTP/1.1, started receiving `403 Client Error: forbidden` responses on token refresh. The `Tesla` class therefore uses `httpx` (installed with the `[http2]` extra so the `h2` package is present) to perform these requests over HTTP/2, automatically falling back to requests over HTTP/1.1 when httpx is unavailable. On Python 2, where httpx cannot be installed, the requests fallback is always used.
 
 The `Tesla` class extends `requests_oauthlib.OAuth2Session` which extends `requests.Session` and therefore inherits methods like `get()` and `post()` that can be used to perform API calls. Module characteristics:
 
@@ -814,7 +816,7 @@ TeslaPy is available on PyPI:
 
 Make sure you have [Python](https://www.python.org/) 2.7+ or 3.5+ installed on your system. Alternatively, clone the repository to your machine and run demo application [cli.py](https://github.com/tdorssers/TeslaPy/blob/master/cli.py), [menu.py](https://github.com/tdorssers/TeslaPy/blob/master/menu.py) or [gui.py](https://github.com/tdorssers/TeslaPy/blob/master/gui.py) to get started, after installing [requests_oauthlib](https://pypi.org/project/requests-oauthlib/) 0.8.0+, [geopy](https://pypi.org/project/geopy/) 1.14.0+, [pywebview](https://pypi.org/project/pywebview/) 3.0+ (optional), [selenium](https://pypi.org/project/selenium/) 3.13.0+ (optional) and [websocket-client](https://pypi.org/project/websocket-client/) 0.59+ using [PIP](https://pypi.org/project/pip/) as follows:
 
-`python -m pip install requests_oauthlib geopy pywebview selenium websocket-client`
+`python -m pip install requests_oauthlib 'httpx[http2]' geopy pywebview selenium websocket-client`
 
 and install [ChromeDriver](https://sites.google.com/chromium.org/driver/) to use Selenium or on Ubuntu as follows:
 
diff --git a/requirements.txt b/requirements.txt
index e00c40e..195edd5 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,5 +1,6 @@
 geopy>=1.20.0
 requests-oauthlib>=1.3.0
 websocket_client>=0.59.0
+httpx[http2]>=0.27.0
 selenium>=3.141.0
 pywebview>=3.2
\ No newline at end of file
diff --git a/setup.cfg b/setup.cfg
index eccc1af..6619ed4 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -33,3 +33,4 @@ install_requires =
     requests >= 2.4.2
     requests_oauthlib
     websocket-client >= 0.59.0
+    httpx[http2] >= 0.27.0
diff --git a/teslapy/__init__.py b/teslapy/__init__.py
index 329f3b6..02b12ab 100644
--- a/teslapy/__init__.py
+++ b/teslapy/__init__.py
@@ -32,8 +32,18 @@
 from requests.packages.urllib3.util.retry import Retry
 from urllib3.poolmanager import PoolManager
 from oauthlib.oauth2.rfc6749.errors import *
+from oauthlib.common import urldecode
 import websocket  # websocket-client v0.49.0 up to v0.58.0 is not supported
 
+# Optional HTTP/2 transport. Since June 2026 Tesla's SSO and Owner API servers
+# require HTTP/2, which `requests` cannot speak, so token refresh fails with a
+# 403. `httpx` is used when available and we fall back to `requests` otherwise.
+try:
+    import httpx
+    HAS_HTTPX = True
+except ImportError:
+    HAS_HTTPX = False
+
 requests.packages.urllib3.disable_warnings()
 
 BASE_URL = 'https://owner-api.teslamotors.com/'
@@ -163,7 +173,12 @@ def request(self, method, url, serialize=True, **kwargs):
         kwargs.setdefault('timeout', self.timeout)
         if serialize and 'data' in kwargs:
             kwargs['json'] = kwargs.pop('data')
-        response = super(Tesla, self).request(method, url, **kwargs)
+        # Use HTTP/2 for Owner API calls when httpx is available, otherwise
+        # fall back to requests (HTTP/1.1 over TLS 1.3 via TLSAdapter)
+        if HAS_HTTPX:
+            response = self._request_http2(method, url, **kwargs)
+        else:
+            response = super(Tesla, self).request(method, url, **kwargs)
         # Error message handling
         if serialize and 400 <= response.status_code < 600:
             try:
@@ -177,6 +192,64 @@ def request(self, method, url, serialize=True, **kwargs):
             return response.json(object_hook=JsonDict)
         return response.text
 
+    @staticmethod
+    def _httpx_auth_verify(verify=True):
+        """ Returns an httpx `verify` value pinned to TLS 1.3 that advertises
+        HTTP/2 over ALPN. Tesla's servers reject connections that do not
+        negotiate TLS 1.3, mirroring the requests `TLSAdapter`. A custom SSL
+        context, CA bundle path or disabled verification is passed through. """
+        if verify is False or isinstance(verify, (str, bytes, ssl.SSLContext)):
+            return verify
+        try:
+            context = ssl.create_default_context()
+            context.minimum_version = ssl.TLSVersion.TLSv1_3
+            # httpx only sets ALPN protocols when it builds the SSL context
+            # itself, so HTTP/2 must be advertised on our custom context
+            context.set_alpn_protocols(['h2', 'http/1.1'])
+            return context
+        except Exception:
+            return verify
+
+    def _httpx_client_kwargs(self, verify):
+        """ Builds `httpx.Client` keyword arguments from the session settings,
+        forwarding the proxy and trust_env configuration. """
+        client_kwargs = {'http2': True, 'trust_env': self.trust_env,
+                         'verify': self._httpx_auth_verify(verify)}
+        proxy = self.proxies.get('https')
+        if proxy:
+            client_kwargs['proxy'] = proxy
+        return client_kwargs
+
+    def _request_http2(self, method, url, **kwargs):
+        """ Sends an Owner API request over HTTP/2 using httpx and returns a
+        requests compatible response. Refreshes an expired access token first,
+        as `OAuth2Session` would for the requests transport, and falls back to
+        requests (HTTP/1.1) when the HTTP/2 request fails. """
+        # Auto-refresh an expired token (OAuth2Session does this for requests)
+        if (not kwargs.get('withhold_token') and self.authorized
+                and 0 < (self.expires_at or 0) < time.time()):
+            self.refresh_token()
+        # Start from the session headers so httpx sends the same fingerprint
+        # (Content-Type, X-Tesla-User-Agent, User-Agent) as the requests session
+        headers = dict(self.headers)
+        if not kwargs.get('withhold_token') and self.authorized:
+            token = self.token.get('access_token')
+            if token:
+                headers['Authorization'] = 'Bearer ' + token
+        request_kwargs = {'headers': headers, 'follow_redirects': True,
+                          'timeout': kwargs.get('timeout', self.timeout)}
+        for key in ('params', 'json', 'data'):
+            if key in kwargs:
+                request_kwargs[key] = kwargs[key]
+        try:
+            with httpx.Client(**self._httpx_client_kwargs(self.verify)) as client:
+                response = client.request(method, url, **request_kwargs)
+            return _HTTP2Response(response)
+        except Exception as exc:
+            logger.warning('HTTP/2 request failed, falling back to HTTP/1.1: %s',
+                           exc)
+            return super(Tesla, self).request(method, url, **kwargs)
+
     @staticmethod
     def new_code_verifier():
         """ Generate code verifier for PKCE as per RFC 7636 section 4.1 """
@@ -241,6 +314,15 @@ def fetch_token(self, token_url='oauth2/v3/token', **kwargs):
             kwargs['authorization_response'] = self.authenticator(url)
         # Use authorization code in redirected location to get token
         token_url = urljoin(self.sso_base_url, token_url)
+        # Try HTTP/2 first as Tesla requires it for auth.tesla.com since 2026
+        if HAS_HTTPX:
+            try:
+                self._fetch_token_http2(token_url, **kwargs)
+                self._token_updater()  # Save new token
+                return self.token
+            except Exception as exc:
+                logger.warning('HTTP/2 token fetch failed, falling back to '
+                               'HTTP/1.1: %s', exc)
         kwargs['include_client_id'] = True
         kwargs.setdefault('verify', self.verify)
         kwargs.setdefault('code_verifier', self.code_verifier)
@@ -248,6 +330,28 @@ def fetch_token(self, token_url='oauth2/v3/token', **kwargs):
         self._token_updater()  # Save new token
         return self.token
 
+    def _fetch_token_http2(self, token_url, **kwargs):
+        """ Exchanges the authorization code for a token over HTTP/2 using the
+        oauthlib client to build the request body and parse the response. """
+        # Extract the authorization code from the redirected location
+        self._client.parse_request_uri_response(
+            kwargs['authorization_response'], state=self._state)
+        body = self._client.prepare_request_body(
+            code=self._client.code, redirect_uri=self.redirect_uri,
+            include_client_id=True,
+            code_verifier=kwargs.get('code_verifier', self.code_verifier))
+        headers = {'Accept': 'application/json',
+                   'Content-Type': 'application/x-www-form-urlencoded'}
+        timeout = kwargs.get('timeout', self.timeout)
+        verify = kwargs.get('verify', self.verify)
+        with httpx.Client(**self._httpx_client_kwargs(verify)) as client:
+            response = client.post(token_url, data=dict(urldecode(body)),
+                                   headers=headers, timeout=timeout)
+            response.raise_for_status()
+            self.token = self._client.parse_request_body_response(
+                response.text, scope=self.scope)
+        return self.token
+
     def refresh_token(self, token_url='oauth2/v3/token', **kwargs):
         """ Overriddes base method to refresh Tesla's SSO token. Raises
         ValueError and ServerError.
@@ -262,11 +366,45 @@ def refresh_token(self, token_url='oauth2/v3/token', **kwargs):
         if not self.authorized and not kwargs.get('refresh_token'):
             raise ValueError('`refresh_token` is not set')
         token_url = urljoin(self.sso_base_url, token_url)
+        # Try HTTP/2 first as Tesla requires it for auth.tesla.com since 2026
+        if HAS_HTTPX:
+            try:
+                self._refresh_token_http2(token_url, **kwargs)
+                self._token_updater()  # Save new token
+                return self.token
+            except Exception as exc:
+                logger.warning('HTTP/2 token refresh failed, falling back to '
+                               'HTTP/1.1: %s', exc)
         kwargs.setdefault('verify', self.verify)
         super(Tesla, self).refresh_token(token_url, **kwargs)
         self._token_updater()  # Save new token
         return self.token
 
+    def _refresh_token_http2(self, token_url, **kwargs):
+        """ Refreshes Tesla's SSO token over HTTP/2 using the oauthlib client
+        to build the request body and parse the response. """
+        refresh_token = (kwargs.get('refresh_token')
+                         or self.token.get('refresh_token'))
+        if not refresh_token:
+            raise ValueError('`refresh_token` is not set')
+        body = self._client.prepare_refresh_body(
+            refresh_token=refresh_token, scope=self.scope,
+            **self.auto_refresh_kwargs)
+        headers = {'Accept': 'application/json',
+                   'Content-Type': 'application/x-www-form-urlencoded'}
+        timeout = kwargs.get('timeout', self.timeout)
+        verify = kwargs.get('verify', self.verify)
+        with httpx.Client(**self._httpx_client_kwargs(verify)) as client:
+            response = client.post(token_url, data=dict(urldecode(body)),
+                                   headers=headers, timeout=timeout)
+            response.raise_for_status()
+            self.token = self._client.parse_request_body_response(
+                response.text, scope=self.scope)
+        # Tesla may omit the refresh token in the response, so preserve it
+        if 'refresh_token' not in self.token:
+            self.token['refresh_token'] = refresh_token
+        return self.token
+
     def close(self):
         """ Overriddes base method to remove all adapters on close """
         super(Tesla, self).close()
@@ -409,6 +547,32 @@ def wall_connector_list(self):
                 if p.get('resource_type') == 'wall_connector']
 
 
+class _HTTP2Response(object):
+    """ Adapts an `httpx.Response` to the subset of the `requests.Response`
+    interface used by `Tesla.request`, so the HTTP/2 path is transparent. """
+
+    def __init__(self, response):
+        self._content = response.content
+        self.status_code = response.status_code
+        self.reason = response.reason_phrase
+        self.headers = response.headers
+
+    @property
+    def text(self):
+        """ Returns the response body decoded as text """
+        return self._content.decode('utf-8', 'replace')
+
+    def json(self, **kwargs):
+        """ Deserializes the response body as JSON """
+        return json.loads(self._content, **kwargs)
+
+    def raise_for_status(self):
+        """ Raises HTTPError, if one occurred """
+        if 400 <= self.status_code < 600:
+            raise HTTPError('%s Client Error: %s' % (self.status_code,
+                                                     self.reason), response=self)
+
+
 class VehicleError(Exception):
     """ Vehicle exception class """
     pass