How to Play 90-Ball Bingo: Tickets, Strips and Odds

A 90-ball ticket is a grid of three rows and nine columns that holds 15 numbers, and the game pays up to three prizes in turn: one line, two lines and a full house. One ticket needs 85.31 balls on average to fill, but British rooms sell tickets in strips of six that cover every number from 1 to 90 once, and a strip is bound to hold a line by ball 73 and a full house by ball 85. This guide shows a ticket and a strip generated by code, the odds of each prize ball by ball, what the size of the room does to a game and the calls that go with it. The odds are our own calculations, and none of them predicts a session you play. Published rules treat 90-ball as the usual British format, so the last sections say what you will see online.

A 90-Ball Ticket, Square by Square

A ticket is a grid of 27 squares, three rows by nine columns. Each row holds five numbers and four blanks, which gives 15 numbers and 12 empty squares. Column 1 takes numbers from 1 to 9, column 2 from 10 to 19, and so on up to column 9, which takes 80 to 90. Some printed tickets move every boundary up by one, so that the columns run 1 to 10, 11 to 20 and so on, and this series uses the 1-9, 10-19 layout. In our tickets a column holds between one and three numbers, rising from top to bottom.

This is ticket 1 of the strip in the next section. Its top row holds 2, 20, 30, 44, 51; its middle row 17, 26, 31, 47, 76; its bottom row 39, 48, 54, 66, 88. The nine columns hold 1, 1, 2, 3, 3, 2, 1, 1 and 1 numbers from left to right.

One Strip, Six Tickets, Ninety Numbers

Six tickets of 15 numbers carry 90 numbers between them, and a strip is built so that each number from 1 to 90 appears once: nine numbers in column 1, ten in each of columns 2 to 8 and eleven in column 9. The table lists our example strip, 18 rows in all, generated and checked by code so that no number repeats. A hire firm that prints these tickets says they usually come six to a sheet.

The column ranges explain why tickets differ. Column 1 has only nine numbers to share among six tickets, so some tickets show a single number there, while column 9 has eleven numbers to share, so some show two or three.

Since the strip holds every number, each call lands on exactly one of its six tickets, and you mark a number on every call. The two guarantees are counting, not luck. After 73 balls only 17 numbers are still in the pot, and each of them can spoil at most one of the 18 rows because no two rows share a number, so at least one row is complete. After 85 balls only 5 numbers remain, and they can spoil at most five of the six tickets, so at least one ticket is full.

Line, Two Lines and Full House

A line is one completed horizontal row of five numbers. Two lines are any two completed rows on the same ticket, and a full house is all 15 numbers. Columns and diagonals do not count, the prizes are paid in that order and the full house closes the game. On a strip a line can come from any of the 18 rows, but two lines must sit on the same ticket, so a second line needs one ticket to do well twice. Some rooms open with a four corners game, which takes the outer numbers of the top and bottom rows, and the hall’s National Bingo Game plays a full house alone.

To see what the prizes are worth, take the reference room: 200 tickets at 1 chip each, an illustrative retention of 20% and a series split of 15%, 25% and 60% between line, two lines and full house. The split is ours and not any room’s rule.

1. 200 tickets at 1 chip bring in 200 chips.
2. The room keeps 20%, which leaves a pot of 160 chips.
3. The pot pays 24 chips for the line, 40 for two lines and 96 for the full house.
4. If two tickets complete the full house on the same ball, each takes 48 chips, and with three tickets each takes 32.

Odds for One Ticket and for a Strip

The table gives the chance that each prize is already complete by a given ball, from exact formulas. Our simulation of 200,000 rounds agrees with them: it averaged 85.32 balls to the full house of one ticket, against the exact 85.31.

Lines arrive early and full houses late. By ball 65, one ticket has a 47.45% chance of holding a line and only 0.453% of being full. On average one ticket needs 64.63 balls for a line, 77.56 for two lines and 85.31 for the full house, while a strip needs 46.56 for a line and 77.53 for the full house.

A strip does slightly better than six separate tickets. By ball 55 its line chance is 82.64% against 77.89% for six independent tickets, and by ball 80 its full house chance is 68.28% against 60.91%, because its rows never share a number.

You can check the last of the ticket figures by hand. For s marked numbers in a pot of N balls, the latest one appears on average at ball s times (N + 1) divided by (s + 1), so for the 15 numbers of a ticket it is 15 times 91 divided by 16, which is 85.31.

How Room Size Changes a Game

One ticket alone misses the race. In a room many tickets compete, and the game ends when the first of them completes the prize. Our model treats a room as N independent tickets, which is a simplification, with the series rooms of 50, 200 and 1,000 tickets.

A bigger room trims the line far more than the full house. Across the three rooms the line falls from 32.15 to 18.85 balls, because a line is a small target that many tickets reach early, while the full house falls from 69.28 to 58.19. The minutes assume a ball every 4 seconds, and one operator guide puts a 90-ball game at roughly four to ten minutes.

To test the simplification we also ran rooms of tickets built the way real ones are. The full house averaged 69.18, 63.89 and 58.21 balls in the three rooms, against 69.28, 63.88 and 58.19 in the model, so the gaps stay under a tenth of a ball. In the 200-ticket model about 11.64% of games end with two or more tickets completing the full house on the same ball.

The Example Draw, Ball by Ball

Our example draw opens 11, 84, 72, 44, 24, 60, 26, 57, 56, 13, 30, 87. Ticket 1 of the strip holds 3 of those numbers after 12 balls and 5 after 30. It completes its first row (the top row, with 2, 20, 30, 44, 51) on ball 56, a second row on ball 70 and the full house on ball 90.

Across the whole strip, the first line came on ball 55, on ticket 3, and the first full house on ball 77, on ticket 4. A 200-ticket room has paid its full house by ball 70 in 95.82% of games, so in this draw the strip would very probably have been beaten to the top prize. What the strip owns is a share of the room, 6 tickets in 200, which is a rough 3.00% chance at a given prize.

Calls and Nicknames

The caller opens with eyes down and announces each number, and British callers add a nickname to many of them. A published list gives Kelly’s eye for 1, Legs eleven for 11, Unlucky for some for 13, Key of the door for 21, Clickety click for 66, Two fat ladies for 88 and Top of the shop for 90. The list says nicknames help called numbers to be clearly understood in a noisy environment and that some date back to 1900. Online, the number shows on screen, and a chat host, if the room has one, may supply the patter.

Pre-Buy, Jackpots and the British Setting

Three features turn up in 90-ball lobbies. Pre-buy lets you buy tickets for a scheduled game in advance, which moves the moment you pay and leaves the odds alone. Fast rooms shorten the wait between games. Many 90-ball sessions also attach a jackpot for a full house within a set number of calls, which glossaries describe in the same terms.

The jackpot is where the table earns its keep. For one ticket the chance of a full house by ball 55 is 0.026%, about 1 in 3,850, and a strip raises that to 0.156%. A 200-ticket room finishes its full house by ball 55 in 5.06% of games in our model, about 1 in 19.7. A tight call limit therefore pays out rarely, and the prizes guide shows what that does to the expected return.

The sources agree on the setting. One rules page calls 90-ball the dominant format in the United Kingdom, another says it is what you would generally find in a UK bingo hall and a third calls it the traditional game. In a hall the caller validates a claim and a night is split into books of pages, and online a generator replaces the ball machine. The how-it-works guide covers the lobby, and the legal guide sets out the Gambling Commission rules that a licensed site follows.

More Guides in This Series

This guide is one of nine. The UK bingo hub sets the four ball counts side by side, and the guides below each take one question.

• How online bingo works: seven steps from pre-buy to payout, what certified should mean and how to read a bonus condition.
• 75-ball bingo: the 5×5 card with a free centre and the chance that each pattern is complete by a given ball.
• 80-ball bingo: the 16-number card, the colours some sites use and the average of 76.24 balls to fill it.
• 30-ball bingo: nine numbers on a 3×3 ticket, 27.9 balls on average and what that does to the hourly bill.
• Prizes and jackpots: fixed, shared, progressive and within-X-calls prizes, with the effect of each on your return.
• How many tickets to buy: why more tickets raise your chance and your cost together, and what a session costs at three retention levels.
• Is online bingo legal in the UK?: the licence register, age and identity checks, complaints, GAMSTOP and the help line.

Pricing a Strip and Setting a Limit

A strip takes 6 chips a game, so 10 games put 60 chips in play before any prize comes back. At the illustrative 20% retention that session costs 12 chips on average, whichever tickets you hold. Choose your limit before the first ball and stop when you reach it. The safer gambling page for Britain has the tools and the support links.

Author:

Lucas Portela

Owner, BoldGambler • Avanhandava/SP

Oddsmaker, affiliate and content creator in the iGaming industry.

LinkedInE-mail