diff --git a/mautrix_telegram/db/portal.py b/mautrix_telegram/db/portal.py
index be8a295d..622a8a66 100644
--- a/mautrix_telegram/db/portal.py
+++ b/mautrix_telegram/db/portal.py
@@ -22,7 +22,7 @@ from asyncpg import Record
 from attr import dataclass
 import attr
 
-from mautrix.types import ContentURI, RoomID
+from mautrix.types import ContentURI, EventID, RoomID
 from mautrix.util.async_db import Database
 
 from ..types import TelegramID
@@ -45,6 +45,10 @@ class Portal:
     avatar_url: ContentURI | None
     encrypted: bool
 
+    sponsored_event_id: EventID | None
+    sponsored_event_ts: int | None
+    sponsored_msg_random_id: bytes | None
+
     # Telegram chat metadata
     username: str | None
     title: str | None
@@ -62,8 +66,8 @@ class Portal:
         return cls(**data)
 
     columns: ClassVar[str] = (
-        "tgid, tg_receiver, peer_type, megagroup, mxid, avatar_url, encrypted, config, "
-        "username, title, about, photo_id"
+        "tgid, tg_receiver, peer_type, megagroup, mxid, avatar_url, encrypted, sponsored_event_id,"
+        "sponsored_event_ts, sponsored_msg_random_id, username, title, about, photo_id, config"
     )
 
     @classmethod
@@ -100,6 +104,9 @@ class Portal:
             self.mxid,
             self.avatar_url,
             self.encrypted,
+            self.sponsored_event_id,
+            self.sponsored_event_ts,
+            self.sponsored_msg_random_id,
             self.username,
             self.title,
             self.about,
@@ -110,8 +117,9 @@ class Portal:
 
     async def save(self) -> None:
         q = (
-            "UPDATE portal SET mxid=$4, avatar_url=$5, encrypted=$6, username=$7, title=$8,"
-            "                  about=$9, photo_id=$10, megagroup=$11, config=$12 "
+            "UPDATE portal SET mxid=$4, avatar_url=$5, encrypted=$6, sponsored_event_id=$7,"
+            "                  sponsored_event_ts=$8, sponsored_msg_random_id=$9, username=$10,"
+            "                  title=$11, about=$12, photo_id=$13, megagroup=$14, config=$15 "
             "WHERE tgid=$1 AND tg_receiver=$2 AND (peer_type=$3 OR true)"
         )
         await self.db.execute(q, *self._values)
@@ -129,8 +137,9 @@ class Portal:
     async def insert(self) -> None:
         q = (
             "INSERT INTO portal (tgid, tg_receiver, peer_type, mxid, avatar_url, encrypted,"
+            "                    sponsored_event_id, sponsored_event_ts, sponsored_msg_random_id,"
             "                    username, title, about, photo_id, megagroup, config) "
-            "VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12)"
+            "VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12, $13, $14, $15)"
         )
         await self.db.execute(q, *self._values)
 
diff --git a/mautrix_telegram/db/upgrade/__init__.py b/mautrix_telegram/db/upgrade/__init__.py
index 146e7134..2146830c 100644
--- a/mautrix_telegram/db/upgrade/__init__.py
+++ b/mautrix_telegram/db/upgrade/__init__.py
@@ -2,4 +2,4 @@ from mautrix.util.async_db import UpgradeTable
 
 upgrade_table = UpgradeTable()
 
-from . import v01_initial_revision
+from . import v01_initial_revision, v02_sponsored_events
diff --git a/mautrix_telegram/db/upgrade/v02_sponsored_events.py b/mautrix_telegram/db/upgrade/v02_sponsored_events.py
new file mode 100644
index 00000000..273319d1
--- /dev/null
+++ b/mautrix_telegram/db/upgrade/v02_sponsored_events.py
@@ -0,0 +1,25 @@
+# mautrix-telegram - A Matrix-Telegram puppeting bridge
+# Copyright (C) 2021 Tulir Asokan
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.
+from asyncpg import Connection
+
+from . import upgrade_table
+
+
+@upgrade_table.register(description="Add column to store sponsored message event ID in channels")
+async def upgrade_v2(conn: Connection) -> None:
+    await conn.execute("ALTER TABLE portal ADD COLUMN sponsored_event_id TEXT")
+    await conn.execute("ALTER TABLE portal ADD COLUMN sponsored_event_ts BIGINT")
+    await conn.execute("ALTER TABLE portal ADD COLUMN sponsored_msg_random_id bytea")
diff --git a/mautrix_telegram/formatter/from_telegram.py b/mautrix_telegram/formatter/from_telegram.py
index 00765b1c..e650f3c7 100644
--- a/mautrix_telegram/formatter/from_telegram.py
+++ b/mautrix_telegram/formatter/from_telegram.py
@@ -43,6 +43,7 @@ from telethon.tl.types import (
     PeerChannel,
     PeerChat,
     PeerUser,
+    SponsoredMessage,
     TypeMessageEntity,
 )
 
@@ -175,7 +176,7 @@ async def _add_reply_header(
 
 
 async def telegram_to_matrix(
-    evt: Message,
+    evt: Message | SponsoredMessage,
     source: au.AbstractUser,
     main_intent: IntentAPI | None = None,
     prefix_text: str | None = None,
@@ -183,6 +184,7 @@ async def telegram_to_matrix(
     override_text: str = None,
     override_entities: list[TypeMessageEntity] = None,
     no_reply_fallback: bool = False,
+    require_html: bool = False,
 ) -> TextMessageEventContent:
     content = TextMessageEventContent(
         msgtype=MessageType.TEXT,
@@ -191,33 +193,34 @@ async def telegram_to_matrix(
     entities = override_entities or evt.entities
     if entities:
         content.format = Format.HTML
-        content.formatted_body = await _telegram_entities_to_matrix_catch(content.body, entities)
+        html = await _telegram_entities_to_matrix_catch(add_surrogate(content.body), entities)
+        content.formatted_body = del_surrogate(html).replace("\n", "<br/>")
 
-    if prefix_html:
+    def force_html():
         if not content.formatted_body:
             content.format = Format.HTML
             content.formatted_body = escape(content.body)
+
+    if require_html:
+        force_html()
+
+    if prefix_html:
+        force_html()
         content.formatted_body = prefix_html + content.formatted_body
     if prefix_text:
         content.body = prefix_text + content.body
 
-    if evt.fwd_from:
+    if getattr(evt, "fwd_from", None):
         await _add_forward_header(source, content, evt.fwd_from)
 
-    if evt.reply_to and not no_reply_fallback:
+    if getattr(evt, "reply_to", None) and not no_reply_fallback:
         await _add_reply_header(source, content, evt, main_intent)
 
     if isinstance(evt, Message) and evt.post and evt.post_author:
-        if not content.formatted_body:
-            content.formatted_body = escape(content.body)
+        force_html()
         content.body += f"\n- {evt.post_author}"
         content.formatted_body += f"<br/><i>- <u>{evt.post_author}</u></i>"
 
-    content.body = del_surrogate(content.body)
-
-    if content.formatted_body:
-        content.formatted_body = del_surrogate(content.formatted_body.replace("\n", "<br/>"))
-
     return content
 
 
diff --git a/mautrix_telegram/matrix.py b/mautrix_telegram/matrix.py
index dd9208db..7ff88c59 100644
--- a/mautrix_telegram/matrix.py
+++ b/mautrix_telegram/matrix.py
@@ -17,6 +17,7 @@ from __future__ import annotations
 
 from typing import TYPE_CHECKING, Iterable
 
+from mautrix.appservice import DOUBLE_PUPPET_SOURCE_KEY
 from mautrix.bridge import BaseMatrixHandler
 from mautrix.errors import MatrixError
 from mautrix.types import (
@@ -35,6 +36,7 @@ from mautrix.types import (
     RoomID,
     RoomNameStateEventContent as NameContent,
     RoomTopicStateEventContent as TopicContent,
+    SingleReceiptEventContent,
     StateEvent,
     TextMessageEventContent,
     TypingEvent,
@@ -128,8 +130,9 @@ class MatrixHandler(BaseMatrixHandler):
                     EventType.ROOM_MESSAGE,
                     TextMessageEventContent(
                         msgtype=MessageType.NOTICE,
-                        body="Portal to private chat created and end-to-bridge"
-                        " encryption enabled.",
+                        body=(
+                            "Portal to private chat created and end-to-bridge encryption enabled."
+                        ),
                     ),
                 )
                 await intent.send_message_event(room_id, evt_type, content)
@@ -352,26 +355,12 @@ class MatrixHandler(BaseMatrixHandler):
                 user, profile.displayname, prev_profile.displayname, event_id
             )
 
-    @staticmethod
-    def parse_read_receipts(content: ReceiptEventContent) -> Iterable[tuple[UserID, EventID]]:
-        return (
-            (user_id, event_id)
-            for event_id, receipts in content.items()
-            for user_id in receipts.get(ReceiptType.READ, {})
-        )
-
-    @staticmethod
-    async def handle_read_receipts(
-        room_id: RoomID, receipts: Iterable[tuple[UserID, EventID]]
+    async def handle_read_receipt(
+        self, user: u.User, portal: po.Portal, event_id: EventID, data: SingleReceiptEventContent
     ) -> None:
-        portal = await po.Portal.get_by_mxid(room_id)
-        if not portal or not portal.allow_bridging:
+        if not portal.allow_bridging:
             return
-
-        for user_id, event_id in receipts:
-            user = await u.User.get_by_mxid(user_id, check_db=False, create=False)
-            if user and await user.is_logged_in():
-                await portal.mark_read(user, event_id)
+        await portal.mark_read(user, event_id, data.get("ts", 0))
 
     @staticmethod
     async def handle_presence(user_id: UserID, presence: PresenceState) -> None:
@@ -402,7 +391,7 @@ class MatrixHandler(BaseMatrixHandler):
         self, evt: ReceiptEvent | PresenceEvent | TypingEvent
     ) -> None:
         if evt.type == EventType.RECEIPT:
-            await self.handle_read_receipts(evt.room_id, self.parse_read_receipts(evt.content))
+            await self.handle_receipt(evt)
         elif evt.type == EventType.PRESENCE:
             await self.handle_presence(evt.sender, evt.content.presence)
         elif evt.type == EventType.TYPING:
diff --git a/mautrix_telegram/portal.py b/mautrix_telegram/portal.py
index 7c4eaa0e..96932023 100644
--- a/mautrix_telegram/portal.py
+++ b/mautrix_telegram/portal.py
@@ -35,6 +35,7 @@ import base64
 import codecs
 import mimetypes
 import random
+import time
 import unicodedata
 
 from asyncpg import UniqueViolationError
@@ -53,6 +54,7 @@ from telethon.tl.functions.channels import (
     InviteToChannelRequest,
     JoinChannelRequest,
     UpdateUsernameRequest,
+    ViewSponsoredMessageRequest,
 )
 from telethon.tl.functions.messages import (
     AddChatUserRequest,
@@ -122,6 +124,7 @@ from telethon.tl.types import (
     Poll,
     SendMessageCancelAction,
     SendMessageTypingAction,
+    SponsoredMessage,
     TypeChannelParticipant,
     TypeChat,
     TypeChatParticipant,
@@ -250,6 +253,14 @@ class Portal(DBPortal, BasePortal):
     _main_intent: IntentAPI | None
     _room_create_lock: asyncio.Lock
 
+    _sponsored_msg: SponsoredMessage | None
+    _sponsored_entity: User | Channel | None
+    _sponsored_msg_ts: float
+    _sponsored_msg_lock: asyncio.Lock
+    _sponsored_evt_id: EventID | None
+    _sponsored_seen: dict[UserID, bool]
+    _new_messages_after_sponsored: bool
+
     def __init__(
         self,
         tgid: TelegramID,
@@ -259,6 +270,9 @@ class Portal(DBPortal, BasePortal):
         mxid: RoomID | None = None,
         avatar_url: ContentURI | None = None,
         encrypted: bool = False,
+        sponsored_event_id: EventID | None = None,
+        sponsored_event_ts: int | None = None,
+        sponsored_msg_random_id: bytes | None = None,
         username: str | None = None,
         title: str | None = None,
         about: str | None = None,
@@ -273,6 +287,9 @@ class Portal(DBPortal, BasePortal):
             mxid=mxid,
             avatar_url=avatar_url,
             encrypted=encrypted,
+            sponsored_event_id=sponsored_event_id,
+            sponsored_event_ts=sponsored_event_ts,
+            sponsored_msg_random_id=sponsored_msg_random_id,
             username=username,
             title=title,
             about=about,
@@ -293,6 +310,12 @@ class Portal(DBPortal, BasePortal):
         self._pin_lock = asyncio.Lock()
         self._room_create_lock = asyncio.Lock()
 
+        self._sponsored_msg = None
+        self._sponsored_msg_ts = 0
+        self._sponsored_msg_lock = asyncio.Lock()
+        self._sponsored_seen = {}
+        self._new_messages_after_sponsored = True
+
     # region Properties
 
     @property
@@ -1190,7 +1213,91 @@ class Portal(DBPortal, BasePortal):
             SetTypingRequest(self.peer, action() if typing else SendMessageCancelAction())
         )
 
-    async def mark_read(self, user: u.User, event_id: EventID) -> None:
+    async def _get_sponsored_message(
+        self, user: u.User
+    ) -> tuple[SponsoredMessage | None, Channel | User | None]:
+        if user.is_bot:
+            return None, None
+        elif self._sponsored_msg_ts + 5 * 60 > time.monotonic():
+            return self._sponsored_msg, self._sponsored_entity
+
+        self._sponsored_msg, t_id, self._sponsored_entity = await putil.get_sponsored_message(
+            user, await self.get_input_entity(user)
+        )
+        self._sponsored_msg_ts = time.monotonic()
+        if self._sponsored_entity is None:
+            self.log.warning(f"GetSponsoredMessages didn't return entity for {t_id}")
+        return self._sponsored_msg, self._sponsored_entity
+
+    async def _send_sponsored_msg(self, user: u.User) -> None:
+        self.log.trace(f"Getting a new sponsored message through {user.mxid}")
+        msg, entity = await self._get_sponsored_message(user)
+        if msg is None:
+            self.log.trace("Didn't get a sponsored message")
+            return
+        if self.sponsored_event_id is not None:
+            self.log.debug(
+                f"Redacting old sponsored {self.sponsored_event_id}"
+                " in preparation for sending new one"
+            )
+            await self.main_intent.redact(self.mxid, self.sponsored_event_id)
+        content = await putil.make_sponsored_message_content(user, msg, entity)
+        self.log.trace("Sending sponsored message")
+        self.sponsored_event_id = await self._send_message(self.main_intent, content)
+        self.sponsored_event_ts = int(time.time())
+        self.sponsored_msg_random_id = msg.random_id
+        self._new_messages_after_sponsored = False
+        self._sponsored_seen = {}
+        await self.save()
+        self.log.debug(
+            f"Sent sponsored message {base64.b64encode(self.sponsored_msg_random_id)} "
+            f"to Matrix {self.sponsored_event_id} / {self.sponsored_event_ts}"
+        )
+
+    @property
+    def _sponsored_is_expired(self) -> bool:
+        return (
+            self.sponsored_event_id is None
+            or self.sponsored_event_ts + 24 * 60 * 60 < int(time.time())
+        ) and self._new_messages_after_sponsored
+
+    async def _try_handle_read_for_sponsored_msg(
+        self, user: u.User, event_id: EventID, timestamp: int
+    ) -> None:
+        try:
+            await self._handle_read_for_sponsored_msg(user, event_id, timestamp)
+        except Exception:
+            self.log.warning(
+                "Error handling read receipt for sponsored message processing", exc_info=True
+            )
+
+    async def _handle_read_for_sponsored_msg(
+        self, user: u.User, event_id: EventID, timestamp: int
+    ) -> None:
+        if user.is_bot:
+            return
+        if self._sponsored_is_expired:
+            self.log.trace("Sponsored message is expired, sending new one")
+            async with self._sponsored_msg_lock:
+                if self._sponsored_is_expired:
+                    await self._send_sponsored_msg(user)
+                    return
+
+        if (
+            self.sponsored_event_id == event_id or self.sponsored_event_ts <= timestamp
+        ) and not self._sponsored_seen.get(user.mxid, False):
+            self._sponsored_seen[user.mxid] = True
+            self.log.debug(
+                f"Marking sponsored message {self.sponsored_event_id} as seen by {user.mxid}"
+            )
+            await user.client(
+                ViewSponsoredMessageRequest(
+                    channel=await self.get_input_entity(user),
+                    random_id=self.sponsored_msg_random_id,
+                )
+            )
+
+    async def mark_read(self, user: u.User, event_id: EventID, timestamp: int) -> None:
         if user.is_bot:
             return
         space = self.tgid if self.peer_type == "channel" else user.tgid
@@ -1200,8 +1307,7 @@ class Portal(DBPortal, BasePortal):
             if not message:
                 self.log.debug(
                     f"Dropping Matrix read receipt from {user.mxid}: "
-                    f"target message {event_id} not known and last message"
-                    " in chat not found"
+                    f"target message {event_id} not known and last message in chat not found"
                 )
                 return
             else:
@@ -1218,6 +1324,8 @@ class Portal(DBPortal, BasePortal):
         await user.client.send_read_acknowledge(
             self.peer, max_id=message.tgid, clear_mentions=True
         )
+        if self.peer_type == "channel" and not self.megagroup:
+            asyncio.create_task(self._try_handle_read_for_sponsored_msg(user, event_id, timestamp))
 
     async def _preproc_kick_ban(
         self, user: u.User | p.Puppet, source: u.User
@@ -2195,11 +2303,15 @@ class Portal(DBPortal, BasePortal):
         content = TextMessageEventContent(
             msgtype=MessageType.TEXT,
             format=Format.HTML,
-            body=f"Poll: {poll.question}\n{text_answers}\n"
-            f"Vote with !tg vote {poll_id} <choice number>",
-            formatted_body=f"<strong>Poll</strong>: {poll.question}<br/>\n"
-            f"<ol>{html_answers}</ol>\n"
-            f"Vote with <code>!tg vote {poll_id} &lt;choice number&gt;</code>",
+            body=(
+                f"Poll: {poll.question}\n{text_answers}\n"
+                f"Vote with !tg vote {poll_id} <choice number>"
+            ),
+            formatted_body=(
+                f"<strong>Poll</strong>: {poll.question}<br/>\n"
+                f"<ol>{html_answers}</ol>\n"
+                f"Vote with <code>!tg vote {poll_id} &lt;choice number&gt;</code>"
+            ),
             relates_to=relates_to,
             external_url=self._get_external_url(evt),
         )
@@ -2588,6 +2700,8 @@ class Portal(DBPortal, BasePortal):
         if not event_id:
             return
 
+        self._new_messages_after_sponsored = True
+
         prev_id = self.dedup.update(evt, (event_id, tg_space), (temporary_identifier, tg_space))
         if prev_id:
             self.log.debug(
diff --git a/mautrix_telegram/portal_util/__init__.py b/mautrix_telegram/portal_util/__init__.py
index 841a46c8..20e0ec41 100644
--- a/mautrix_telegram/portal_util/__init__.py
+++ b/mautrix_telegram/portal_util/__init__.py
@@ -3,3 +3,4 @@ from .media_fallback import make_contact_event_content, make_dice_event_content
 from .participants import get_users
 from .power_levels import get_base_power_levels, participants_to_power_levels
 from .send_lock import PortalSendLock
+from .sponsored_message import get_sponsored_message, make_sponsored_message_content
diff --git a/mautrix_telegram/portal_util/sponsored_message.py b/mautrix_telegram/portal_util/sponsored_message.py
new file mode 100644
index 00000000..3440e63b
--- /dev/null
+++ b/mautrix_telegram/portal_util/sponsored_message.py
@@ -0,0 +1,95 @@
+# mautrix-telegram - A Matrix-Telegram puppeting bridge
+# Copyright (C) 2021 Tulir Asokan
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.
+from __future__ import annotations
+
+import base64
+import html
+
+from telethon.tl.functions.channels import GetSponsoredMessagesRequest
+from telethon.tl.types import Channel, InputChannel, PeerChannel, PeerUser, SponsoredMessage, User
+
+from mautrix.types import MessageType, TextMessageEventContent
+
+from .. import user as u
+from ..formatter import telegram_to_matrix
+
+
+async def get_sponsored_message(
+    user: u.User,
+    entity: InputChannel,
+) -> tuple[SponsoredMessage | None, int | None, Channel | User | None]:
+    resp = await user.client(GetSponsoredMessagesRequest(entity))
+    if len(resp.messages) == 0:
+        return None, None, None
+    msg = resp.messages[0]
+    if isinstance(msg.from_id, PeerUser):
+        entities = resp.users
+        target_id = msg.from_id.user_id
+    else:
+        entities = resp.chats
+        target_id = msg.from_id.channel_id
+    try:
+        entity = next(ent for ent in entities if ent.id == target_id)
+    except StopIteration:
+        entity = None
+    return msg, target_id, entity
+
+
+async def make_sponsored_message_content(
+    source: u.User, msg: SponsoredMessage, entity: Channel | User
+) -> TextMessageEventContent | None:
+    content = await telegram_to_matrix(msg, source, require_html=True)
+    content.external_url = f"https://t.me/{entity.username}"
+    content.msgtype = MessageType.NOTICE
+    sponsored_meta = {
+        "random_id": base64.b64encode(msg.random_id).decode("utf-8"),
+    }
+    if isinstance(msg.from_id, PeerChannel):
+        sponsored_meta["channel_id"] = msg.from_id.channel_id
+        if getattr(msg, "channel_post", None) is not None:
+            sponsored_meta["channel_post"] = msg.channel_post
+            content.external_url += f"/{msg.channel_post}"
+            action = "View Post"
+        else:
+            action = "View Channel"
+    elif isinstance(msg.from_id, PeerUser):
+        sponsored_meta["bot_id"] = msg.from_id.user_id
+        if msg.start_param:
+            content.external_url += f"?start={msg.start_param}"
+        action = "View Bot"
+    else:
+        return None
+
+    if isinstance(entity, User):
+        name_parts = [entity.first_name, entity.last_name]
+        sponsor_name = " ".join(x for x in name_parts if x)
+        sponsor_name_html = f"<strong>{html.escape(sponsor_name)}</strong>"
+    elif isinstance(entity, Channel):
+        sponsor_name = entity.title
+        sponsor_name_html = f"<strong>{html.escape(sponsor_name)}</strong>"
+    else:
+        sponsor_name = sponsor_name_html = "unknown entity"
+
+    content["net.maunium.telegram.sponsored"] = sponsored_meta
+    content.formatted_body += (
+        f"<br/><br/>Sponsored message from {sponsor_name_html} "
+        f"- <a href='{content.external_url}'>{action}</a>"
+    )
+    content.body += (
+        f"\n\nSponsored message from {sponsor_name} - {action} at {content.external_url}"
+    )
+
+    return content
diff --git a/requirements.txt b/requirements.txt
index b7974c74..17d14e42 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -3,7 +3,7 @@ python-magic>=0.4,<0.5
 commonmark>=0.8,<0.10
 aiohttp>=3,<4
 yarl>=1,<2
-mautrix==0.14.0rc1
+mautrix==0.14.0rc2
 #telethon>=1.24,<1.25
 # Fork to make session storage async
 tulir-telethon==1.25.0a1