CAS is a global database of confirmed Telegram spammers. With it on, a listed account is blocked the moment it tries to join — before its first message. It is one of several protection layers and it works instantly. Available on every plan; turn it on per group in settings.
Want to set this up? Do it right in your Telm account.
Open in your dashboard1What CAS is
CAS (Combot Anti-Spam) is a worldwide, community-maintained database of Telegram accounts confirmed as spammers. Communities across Telegram report abusers into it.
The value is simple: the same spam accounts roam thousands of groups, and normally each group fights them alone. With CAS you benefit from everyone else's experience — ban once, block everywhere.
2How it works
The check happens at the entrance. When a new member joins, the bot looks them up in CAS. A listed spammer is stopped before they can post anything.
It is one of the first lines of your layered protection — it removes a large share of attacks before any message is even written, so the rest of your protection has less to deal with.
3How the list stays current
CAS is not a static file. It is continuously updated as groups across Telegram report abusers, and Telm keeps its copy in sync so a freshly listed account is recognised quickly.
Because the list is fed by a huge network of communities, a spammer who gets banned in one popular group is often already unable to join yours minutes later.
- Maintained by the wider Telegram anti-spam community, not one group.
- Kept in sync so newly listed accounts are caught promptly.
- Covers serial abusers who hop from community to community.
4What it stops
CAS covers accounts already confirmed as spammers elsewhere on Telegram.
- Serial spam accounts that hop between many communities.
- Known abusers before they post their first message in your group.
5Turning it on
CAS is a per-group toggle. It is on by default — you can switch it off per group if your community is closed and invite-only, but it is safe and low-risk to enable, and there is no reason to leave it off.
6Good to know
CAS only covers accounts that have already been reported and confirmed elsewhere. Brand-new or first-time spammers will not be in it yet — that is exactly what the other layers are for.
For spammers that CAS does not know about, Telm adds its own cross-group database and federated bans, plus rules, the ML model and AI.
7Best practices
CAS is one of the easiest wins in the whole product — a few habits make it even stronger.
- Turn it on for every group; it blocks known attackers before they post.
- Do not rely on CAS alone — pair it with the global spam database (Basic and up) and the rule and model layers for accounts CAS has not seen.
- If a genuine member is ever blocked, the action is reversible through appeals.
- Combine with new-member restrictions and captcha to slow down accounts too new to be on any list.