In the card game contract bridge, Gambling 3NT is a special treatment of an opening bid of 3NT. The bid is used to describe a hand containing a minor suit of at least seven cards in length and headed by the ace, king and queen, at minimum. The bid has the dual objectives of preempting the opponents' bidding should they hold the majors and trying for a game in notrump on the gamble that partner might hold adequate support.
Because this conventional bid replaces the standard use of opening 3NT (a hand with 25-27 high card points and a balanced distribution), partnerships must use other bids to show the standard 3NT hand. For partnerships which also employ the use of the strong two club convention, that bid can be used to describe a standard 3NT opening hand. For example, the following bidding sequence:
| North | East | South | West |
|---|---|---|---|
| 2♣ | Pass | 2♦ | Pass |
| 3NT | Pass | Pass | Pass |
replaces the traditional 3NT opening bid if gambling 3NT and strong two club is in use. That is, North's hand is best described as 25 to 27 high card points and a balanced distribution.