Colors on the Card (Article ID 14)
Abstract: The NMJL card is color-coded to indicate how many suits are needed in a hand. If a hand shows all one color, it means it must play the hand with one suit. Some hands do not have enough room to indicate one suit only; however, if the hand is one color it should be one suit. If a hand in three colors it would use all three suits unless otherwise noted in the parentheses.
The colors on the card do not need to match the color of the suited tiles. For example, the green color on the card does not indicate somebody must use Bams. The color-coding on the card merely shows how many suits are required. If a hand is shown in two or three colors, it means you can use two or three suits for the hand. Players should always look at what’s written in parentheses after the hand to find exceptions to the rules.
Question from a player: Do the suits correspond to the colors on the card? Also, the Consecutive Run category has a hand shown in one suit with a corresponding dragon followed by “any 5 consec. Nos” but why doesn’t it say, “any one suit”?
Answer from the NMJL: “A specific color on the card does not specify a particular suit. For example, if a hand is shown in 3 colors, it means any 3 suits IN ANY ORDER.”
Source: Mah Jongg Made Easy 2020 page 12, para. 1
Other answers from the NMJL:
“Three colors are shown to represent any three different suits, in any order.”
“When a hand is shown in only one color, the hand is played in one suit. It does not say, “any 1 suit” because there is not always enough room on the card to indicate all instructions for a hand. Two colors indicate 2 suits, 3 colors indicate 3 suits. The color coding on the card never dictates witch suits must be played but indicates how many suits are to be included.”
Source for other answers: National Mah Jongg League Bulletin Q&A (2015, 2019) https://www.nationalmahjonggleague.org