Dominoes / Rules
Do doubles have to be played crossways in dominoes?
No. Playing doubles crossways is a convention, not a rule every game shares. Most written rules lay them crossways: pagat.com's Block and Draw games, the Latin American partnership game ("conventionally played at right angles") and Jamaican partner ("traditionally played at right angles"). In those matching games the direction changes nothing about play. It starts to matter in two situations: when the game scores the open ends, because a crossways double at an end counts both halves, and when a double is a spinner that opens new lines of play. Which doubles spin is where the games really differ, so that is what to agree before the first tile.
Which games lay doubles crossways, and which let them spin
Every rule below comes from the pagat.com page for that game (Joe Celko and John McLeod), except where another source is named.
| Game | How doubles go down | Spinners |
|---|---|---|
| Block and Draw (pagat) | Across the line | None |
| Latin American partnership (pagat) | At right angles, by convention | None described |
| Jamaican partner (pagat) | At right angles, by tradition | None described |
| Muggins (pagat) | Crossways | None |
| Fives and Threes (pagat) | Crossways | None |
| All Fives (pagat) | Crossways | The first double played only |
| Sebastopol (pagat) | Across the line | The opening [6-6] only |
| Five Up (pagat) | As spinners | Every double |
| Chicken Foot (pagat) | Always crossways | Every double sprouts three toes |
| Mexican Train (pagat) | Either way | None after the engine |
The table shows the pattern: crossways is close to universal in written rules, but the number of spinners runs from none to every double. Pagat's page on the fives family names the three layouts directly: no spinners gives a single line (Muggins), one spinner gives a cross (All Fives), and every double spinning gives a tree (Five Up, which pagat says is played in the southwestern United States).
In block and draw games, the direction changes nothing
In a plain matching game, a double has the same number on both halves, so it leaves exactly the same number open whichever way you lay it. Put a [4-4] on a 4 end and the end is still a 4. Pagat's Block and Draw pages say doubles go "across the line, but are not spinners", so a crossways double opens no extra ends. The same holds at most partnership tables.
What the crossways habit does give you is a marker. A double standing across the line is easy to spot when you are counting which tiles of a number are gone. If you track tiles by counting halves on the table, as in how to keep track of which dominoes have been played, a double counts the same whether it lies in line or across.
Wikipedia adds one practical exception that every table knows: players turn the line at right angles when it gets close to the edge of the table. That turn is about space, not scoring, and it changes nothing either.
In scoring games, a crossways double at an end counts both halves
In games that score the open ends, a double placed crossways at an end counts its whole pip total. Pagat's Fives and Threes rules say doubles "are turned crosswise and when at an end of the layout count as the total of their pips". Muggins and All Fives say the same: [5-5] at an end counts 10, [6-6] counts 12.
That is where the big plays come from:
- Muggins (pagat): a [6-6] at one end and a [4-4] at the other make 12 + 8 = 20, the highest single play in a game with no spinners.
- Fives and Threes (pagat): a [6-6] at one end and a 3 at the other make 15, which is three fives and five threes, worth 8 points.
- All Fives (pagat): with a spinner adding two more arms, the highest single play is 35 points.
Pagat's rules describe only crossways doubles in these games, so they say nothing about a double laid in line. If your table lays doubles in line to save space, decide first whether an in-line double at an end still counts both halves. Most players assume it does, but it is worth saying out loud, because the answer moves points (see the worked example below).
Spinners: when a double opens new lines
A spinner is a double that can be played on from all four sides, so the line branches. Games differ on which doubles spin, and in what order you may play on them.
- All Fives (pagat): only the first double played is the spinner, and it does not have to be the lead. The first two tiles played against it go on its two long sides; only then can tiles go on its ends, opening a third and fourth arm. Both halves of the spinner count until both sides are covered, then it stops counting. The full sequence is worked through in how to play All Fives.
- Sebastopol (pagat): the [6-6] opens the hand in the centre as a spinner with four arms, and each player in turn adds a six to a different side until all four arms are started. Other doubles go across the line and do not branch.
- Five Up (pagat): every double is a spinner. The first two tiles against a double go on its sides, and as long as one side is free, the double counts the pips on both exposed ends. Layouts grow into trees, and the arithmetic gets harder with every double.
Chicken Foot and Mexican Train have their own double rules
Two popular train-style games turn doubles into the centre of the play.
- Chicken Foot (pagat): doubles are "always placed crosswise". The opening double must get a tile on all four arms before any arm grows. Every later double becomes a chicken foot: three tiles angled outward must be played on it before anyone may play anywhere else. Pagat records a variant where the opening double takes three tiles on each side.
- Mexican Train (pagat): you may lay a double either way. Pagat says some players prefer crosswise, but doubles in this game "do not create a junction". What matters is covering: after a double, the next tile played must go on it. Rule sheets disagree on who has to cover it, as explained in how to play Mexican Train.
Worked example: one double, four rule sets
The line has a 2 at one end. You play the [4-4] on the other end. In All Fives the spinner is already on the table, so this double is not a spinner.
| Rule set | What the ends count | What you score |
|---|---|---|
| Block or Draw (pagat) | Nothing is counted | Nothing; the ends are now 4 and 2 |
| Muggins or All Fives (pagat), crossways | 8 + 2 = 10 | 10 points |
| Fives and Threes (pagat), crossways | 8 + 2 = 10 | 2 points (two fives) |
| A house rule where an in-line double counts one half | 4 + 2 = 6 | 0 in Muggins; 2 points (two threes) in Fives and Threes |
The tile and the position are the same in every row. Only the agreement about the double changes the score, which is why two tables can play "the same game" and disagree. The wider story of how scoring differs is in how is a domino game scored.
House rules to agree before the first tile
Five questions settle almost every argument about doubles:
- Crossways or in line? In a block or partnership game this is only habit. In a scoring game, decide whether an in-line double at an end counts both halves.
- Does any double spin? None (Muggins, Block), the first double played (All Fives), the opening [6-6] (Sebastopol), or every double (Five Up).
- Sides before ends? Pagat's All Fives and Five Up both fill the two long sides of a spinner before its ends.
- When does a spinner stop counting? In pagat's All Fives, once both sides are covered.
- Must a double be covered? Yes in Mexican Train and Chicken Foot, with different rules about who covers it and when.
If nobody at the table knows, pick the pagat version of the game you are playing and say so before you shuffle. For the rest of the rules that change from one table to the next, see the main domino games and how they differ.