System Bets Explained: How a 2 from 3 Ticket Works

A system bet is several bets built from combinations of your selections. It is not a staking progression that increases stakes after losses, or a system for predicting results. One ticket contains multiple parlays, also called accumulators, and some formats include singles.

A system can pay out even when not every selection wins. However, that return may not cover the cost of the ticket. To calculate net profit, subtract all original stakes, not just the stake on the winning combination.

What does a system m/n mean?

A system m/n includes every m-selection combination from n selections. For example, a 2/3 system contains three two-selection accumulators, while a 3/5 system contains ten three-selection accumulators.

With selections A, B and C, a 2/3 system consists of:

• AB;
• AC;
• BC.

In a 3/5 system, each combination contains three of the five selections. There are 10 combinations in total.

Under ordinary win/lose settlement with no void selections, exactly m winners produce one paying combination. Fewer than m winners produce no return; more than m winners produce multiple paying combinations.

That is a condition for receiving a payout, not for making a profit. One winning pair in a 2/3 system can return less than you staked across all three pairs.

How much does a system bet cost?

The total stake equals the number of combinations multiplied by the unit stake—the stake on each combination. For a system m/n, the combination count is:

C(n,m) = n! / (m! × (n − m)!).

A 2/3 system has three combinations. At $10 per combination, the total stake is $30. A 3/5 system has ten combinations, so the same $10 unit stake requires $100.

Before confirming a bookmaker's ticket, check what its stake field means:

The FON help page describes dividing a total stake among combinations. Do not assume another bookmaker uses the same field convention: check the final ticket total.

If the total cannot be divided equally at the operator's permitted currency precision, check how stakes are rounded. In this example, $30 divides evenly into three $10 stakes, so no rounding is needed.

A 2 from 3 example: gross return and net profit

With decimal odds of A — 2.00, B — 1.50 and C — 1.70, a 2/3 system at $10 per combination costs $30 and returns $89.5 if all three win. The net profit is $59.5.

This is a hypothetical example, not a set of real matches. It assumes equal stakes and ordinary win/lose results, with no taxes, bonuses, cash-out or special settlement adjustments such as dead heats. Figures are shown without additional rounding.

Multiply the decimal odds within each accumulator:

Gross return includes the winning stake. Net profit is the combined gross return minus the full $30 ticket cost.

Two winners therefore give different outcomes: from a $4.5 loss to a $4 profit. With just one winning pair, its combined odds must be at least 3.00 to recover the $30 total stake when each combination costs $10. They must exceed 3.00 to produce a profit.

How to repeat the example in the calculator

Open the round robin calculator, enter the three decimal odds, select only two-selection combinations and set a $10 unit stake. The tool calculates the ticket cost and returns for its supported scenarios.

1. Open the calculator and choose decimal odds.
2. Enter 2, 1.5 and 1.7 in the three selection odds fields.
3. In the combination-size controls, leave only size 2 selected.
4. Turn off the option to include singles.
5. Enter 10 in the unit-stake field.
6. Use the Pro control to view the combination list.

Round robin calculator inputs with three decimal odds, size 2 selected and a unit stake of 10

The English-language calculator running on localhost with a hypothetical example: odds of 2, 1.5 and 1.7, pairs only, with singles switched off.

Check the calculation: three combinations, a $30 total stake and a $89.5 gross return if all selections win. With exactly two winners, the possible gross returns range from $25.5 to $34. This range describes different winning pairs; it is neither a promised result nor a probability estimate.

Pro combination list showing Selection 1 + 2 at odds 3.00 with payout 30, Selection 1 + 3 at odds 3.40 with payout 34, and Selection 2 + 3 at odds 2.55 with payout 25.50

The English-language calculator running on localhost: the Pro list shows the three pairs in the hypothetical example and each pair’s payout if it wins.

There is no control here for marking individual selections as won or lost. The calculator also does not calculate void selections or bankers.

For a deeper explanation of the formulas, see how to calculate a system bet.

Singles, a system or one accumulator?

At the same $30 total stake, these options produce different returns and respond differently to one losing selection. For a fair comparison, use the same odds: A — 2.00, B — 1.50 and C — 1.70.

• Three singles: $10 each on A, B and C.
• A 2/3 system: $10 each on AB, AC and BC.
• One three-selection accumulator: $30 on ABC.

The single accumulator gives the largest return when all three win, but a loss by C reduces its return to zero. The system retains the winning AB pair, although here it only recovers the total budget. Singles produce a $5 profit with the same results.

These two scenarios do not establish that one format is always better. See the system bet vs accumulator comparison for more detail.

What are full-cover bets?

Full-cover bets include combinations of several sizes, rather than only one fixed size m. Some also include singles. A Trixie is therefore not the same as a 2/3 system.

A 2/3 system contains only the three pairs. A Trixie adds one three-selection accumulator, making four bets in total.

The following standard formats are described in William Hill's bet types guide. These are ordinary win-only formats; size 1 means singles.

The chart shows combination counts, not payouts. Its logarithmic scale means equal spacing does not represent equal increases in the number of bets.

With a fixed unit stake, the budget grows as the number of combinations increases. With a fixed total budget, each combination receives a smaller stake, reducing its potential return.

For a separate 11-bet example, see the Yankee guide.

What happens when a selection is void?

Under the cited operators' rules, a void selection is settled at odds of 1.00 within the original combinations. Do not simply remove it and rebuild the system as a new ticket containing the remaining selections.

This treatment is stated in FON's rules, §4.6. Technical odds of 1.00 for a refund are also described in Tower's rules, §2.25, PDF page 6. These are operator-specific rules, not a universal settlement rule for every ticket.

The original English source excerpt is shown below:

Original English excerpt from Tower's Betting Rules 2.0, section 2.25, describing technical odds of 1.00 for a refunded bet

Original English excerpt from Tower's Betting Rules 2.0, §2.25. Viewed 2026-10-09; the effective date is unspecified.

In our example, A and B win and C is void. The original $10 stakes on AB, AC and BC remain:

Net profit is $35: subtract all $30 of original stakes from the $65 gross return. If A wins, B loses and C is void, only AC pays, returning $20 for a net loss of $10.

These examples use the stated 1.00 rule and exclude bonuses and taxes. Check your bookmaker's rules before calculating a real ticket; the calculator described above does not handle void settlement.

What is a banker in a system bet?

A banker is a mandatory selection included in every combination of the relevant system. If it loses, all combinations containing it lose. It is not insurance.

This behaviour is described in Betano's banker system help page. Check whether your operator offers the feature and how its ticket is constructed. Adding a banker changes the combinations, so an ordinary system calculation without one cannot simply be applied to that ticket.

What should you check before confirming the ticket?

Check the combinations, total stake and operator's rules before placing the bet. A system's name alone does not confirm that your selections are eligible or that settlement will match this example.

• Confirm the intended combination sizes and whether singles are included.
• Distinguish the total stake from the unit stake, and verify the final ticket cost.
• Check market eligibility and restrictions on related selections. Tower's rules, for example, address related-outcome restrictions in §2.11.
• Check minimum and maximum stakes, payout limits and other operator restrictions.
• Review void rules and bonus conditions for your own ticket.

System combinations overlap: AB and AC both contain A. They are therefore not statistically independent bets—a single losing selection can eliminate several combinations at once.

Set an affordable budget first, then choose the format. A system changes how stakes and potential returns are distributed, but it does not guarantee a net profit.