| Mode | Description | Restrictions |
|---|
| +c | No color allowed in the channel. Will block ANSI and mIRC color codes. | +o or higher |
| +C | No CTCP's allowed in the channel. | +o or higher |
| +D | Delays someone's JOIN message until that person speaks. Chanops and higher, opers and ulines/services are exempt. | +o or higher |
| +F | Flood protection. Set an anti flood profile see channel mode +F. | +o or higher |
| +f | Flood protection fine-tuning. This is a highly advanced feature, see channel mode +f. | +o or higher |
| +G | Filter out bad words configured in Badword block | +o or higher |
| +H | Turns on Channel History. For more information how to use this see Channel history | +o or higher |
| +i | Invite only. Requires people to be /INVITE'd to the channel or be on the +I (Invite Exceptions) list (for that latter, see the List modes section above). | +o or higher |
| +k | Require users to specify a channel key in order to join (/JOIN #chan key). Example: +k secret | +h or higher |
| +K | /KNOCK command is not allowed. | +o or higher |
| +L | If unable to join, user will be forwarded to this channel. Example: +L #something | +o or higher |
| +l | Limit the amount of users that may be in the channel. If the limit is reached then any new JOIN's are rejected (see also +L above). | +o or higher |
| +m | Moderated channel. Only people with +v or higher (+vhoaq) may speak. | +h or higher |
| +M | Must be authenticated to services or have +v or higher to speak. | +o or higher |
| +N | No nick-changes permitted. Normally not set, only during a a nick-flood flood attack. | +o or higher |
| +n | No external messages. If you don't set +n then users outside the channel may still send messages to it. Thus, almost everyone will set their channel +n. | +h or higher |
| +p | Private channel. Partially conceals the existence of the channel. Users cannot see this channel name unless they are a member of it. For example, if you WHOIS a user who is on a +p channel, this channel is omitted from the response - unless you are on the same channel. IRC Operators will always see +p channels and its members. | +o or higher |
| +Q | No /KICK allowed. Can be used to force all chanops to use Services for kicking. Unusual, but possible. | +o or higher |
| +R | Only registered users may join the channel. Registered users are users authenticated to Services. | +o or higher |
| +s | Secret channel. Extends the functionality of +p (above), but in addition to this, it will act as if the channel does not exist at all for queries like /TOPIC, /LIST and /NAMES. One exception to this is that it will always respond to the /MODE command. IRC Operators will always see +s channels and its members. | +o or higher |
| +S | Strip color codes. This removes any mIRC or ANSI color codes by converting it to regular text. | +o or higher |
| +T | Channel notices are not permitted (/NOTICE #chan hi!). On many clients a beeping sound will happen on notices, hence why this mode is sometimes set. | +o or higher |
| +t | Restricts /TOPIC to +h or higher. Without +t anyone in the channel may set the topic. Most channels are +t. | +o or higher |
| +V | /INVITE is not permitted. | +o or higher |
| +z | Only clients which are connected through SSL/TLS may join the channel | +o or higher |
