Can you change an exposure after you make it?
By Jerry Chen. Checked and updated November 1, 2026
Short answer: no, once you have discarded
Not after your discard. Until then you can adjust it; once you have discarded, the exposure is locked and a pung cannot later become a kong. The only later change is a joker being redeemed from it.
The detail
Before your discard (and before you redeem a joker), you can add to or take away from the exposure you just made. The League's January 2025 bulletin also lets you fix an exposure of mismatched tiles until you discard.
After the discard, no changes.
Sources
These follow standard National Mah Jongg League rules. House rules vary; agree on them before you play.
Related questions
- When can you exchange a joker?
- Can you call a discard for a pair?
- How long do you have to call a discard?
- Who gets the discard if two players call it?
- Can you add to an exposure later?
- Can you call a discard if your hand is concealed?
- Can you take back a tile you just discarded?
See more questions in Calling discards and exposures, the complete rules, or all 52 rule questions.