MahjCove · Rules & Strategy
When Can You Call a Discard in American Mahjong?
When to say “call,” where to put the tile, and how long you have to decide.
Someone discards the 5 bam you have been waiting for. Before you reach for it, check what it actually completes: a pung or kong your hand requires, or the whole hand for mahjong. If it only gets you closer — not all the way — you have to leave it.
Under NMJL rules, only the current live discard can be called. Everything thrown earlier is locked on the table, no matter how much you need it.
What you can call for
For an ordinary call, the tile must complete a matching group required by an exposed hand on your card: a pung, kong, quint, or sextet. You must already have the other tiles needed, including any eligible jokers.
You cannot call a tile to fill a single or pair unless it completes mahjong. You also cannot call a tile just to store it for later or to exchange it for an exposed joker.
| Situation | May you call? |
|---|---|
| A 4 bam completes a required pung for your exposed hand | Yes, while the discard is live |
| A north completes a pair, but your hand still needs another tile | No |
| A north completes the pair and the entire legal hand | Yes, for mahjong |
A concealed hand cannot use an ordinary exposure call. It can use a natural discard that completes the whole hand. A discarded joker cannot be called in either situation.
From “call” to exposure
- Check the face of the tile as well as its announced name.
- Say “call” or “mahjong” clearly, as appropriate.
- Place the called tile on top of your rack.
- For an ordinary call, display the complete matching group. For a win, display the complete hand.
- After an ordinary exposure, discard one tile. After a valid mahjong, do not discard.
The League’s January bulletin explicitly requires a tile called for either an exposure or mahjong to be placed on top of the rack. Do not leave a winning discard sitting on the table.
Saying “call” and claiming the tile are separate steps. You commit when you put the called tile atop your rack or start exposing matching tiles. After that, you cannot change your mind and give the discard back. See question 12 and the new-rule box.
Timing and priority
Picking up the next wall tile does not, by itself, close the previous discard to other players. Racking that tile, initiating a joker exchange after the draw, discarding, or declaring mahjong with the drawn tile closes the opportunity.
If another player makes a valid call while the window is still open, the interrupted player returns the wall tile to its original position. That does not mean the drawing player is free to put back a moved tile simply because they change their own mind.
If a call and racking happen at the same time, the call takes precedence. Give the table a moment to respond to each discard; fast racking makes a learning game needlessly difficult.
When two players want the same live discard, a mahjong call takes priority over a call for an ordinary exposure. For two calls of the same type, turn order generally gives priority to the player nearest the discarder in the direction of play. That priority ends if the other player has already claimed the tile or begun exposing. The 2026 bulletin confirms that when both calls are for mahjong, a player who has already begun the winning exposure also affects priority.
Being next in turn does not let you wait indefinitely. Speak up before another player commits to the claim.
Whose turn comes next?
After a player makes an ordinary exposure and discards, play continues with the player to their right. This can skip players who would otherwise have had a turn.
Once the exposure is fixed, its tiles and group size must fit any line you switch to later. Before calling, make sure you are comfortable committing to that group.
Quick answers
May I call a discard for a pair?
Only when that tile completes the whole winning hand. You cannot expose a pair as an ordinary call.
Can I call after the next player merely picks up a tile?
Another player may still call while the opportunity remains open. Picking alone is different from racking or the other closing actions described above.
