# How a Five-Pick Round Robin Works: Pairs, Triples, and Payouts

> Learn how round robin betting works with five picks, 10 pairs and 10 triples, total stakes, gross returns, net results, and calculator checks.

- Source: https://toolsgambling.com/blog/round-robin-betting
- Publisher: ToolsGambling
- Updated: 2026-10-15
- Cite as: "Round Robin By 2s and 3s: Five-Pick Payouts", ToolsGambling, https://toolsgambling.com/blog/round-robin-betting

In US sportsbook usage, a **round robin is a set of separately staked parlays built from your picks**, using the combination sizes you select, such as By 2s or By 3s. Five picks produce **10 two-pick parlays or 10 three-pick parlays**. At \$2 per parlay, either set costs \$20; selecting both creates 20 parlays with a total stake of \$40. This differs from the usage at some UK bookmakers, where Round Robin means a fixed 10-bet system with three selections, as shown in [Betfred’s official Round Robin calculator](https://insights.betfred.com/bet-calculator/round-robin/).

A round robin can return money even when some picks lose, but that does not guarantee a profit. In the hypothetical example below, three of five picks win. The pairs return \$18.60 gross for a net loss of \$1.40; the triples return \$10.80 gross for a net loss of \$9.20.

## What do “By 2s” and “By 3s” mean?

`By 2s` means all two-pick combinations, while `By 3s` means all three-pick combinations. Each combination is a separate parlay with its own stake.

The number of combinations is **C(n,k) = n! / [k!(n−k)!]**, where n is the number of picks and k is the number of picks in each parlay.

| Picks on the slip | `By 2s`: all pairs | `By 3s`: all triples |
|---|---:|---:|
| 4 | 6 parlays | 4 parlays |
| 5 | 10 parlays | 10 parlays |

Five picks happen to produce the same number of pairs and triples. That does not make the tickets equivalent: their combinations and potential returns differ.

[DraftKings’ round robin explanation](https://support.draftkings.com/dk/en-us/what-is-a-round-robin-rr-bet?id=kb_article_view&sysparm_article=KB0010785) describes separately staked pairs and notes that choosing all combinations adds another parlay size. [bet365’s explanation](https://news.bet365.com/en-us/article/what-is-a-round-robin-bet/2026051115471060553) also discusses choosing a combination size and staking each parlay. Check which sizes you selected rather than relying on the number of picks alone.

## What assumptions does this five-pick example use?

This example uses five hypothetical, compatible picks at decimal odds, with **A, B, and C winning and D and E losing**. The stake is **\$2 per parlay**, not \$2 for the whole ticket.

| Pick | Decimal odds | Result |
|---|---:|---|
| A | 2.00 | Win |
| B | 1.80 | Win |
| C | 1.50 | Win |
| D | 2.20 | Loss |
| E | 1.60 | Loss |

This is not an actual wager or an offer to bet at these odds. It assumes ordinary win-or-loss settlement, with no voided picks, bonuses, taxes, payout limits, or operator-specific rounding differences. Potential returns are displayed to the nearest cent; the rounded BDE figure is noted below.

A parlay wins only if every pick in it wins. Its **gross return** equals the stake per parlay multiplied by the decimal odds of every pick in that combination. Gross return includes the winning parlay’s stake. To find the **net result**, subtract the total original stake across all component parlays—not just the stakes on the winners.

For either size alone, the total stake is C(5,k) × \$2 = **\$20**.

## By 2s: which of the 10 pairs win?

**AB, AC, and BC win**, producing a gross return of **\$18.60**. The other seven pairs contain D or E and return nothing.

For example, AB returns \$2 × 2.00 × 1.80 = **\$7.20**.

| Parlay | Potential gross return if it wins | Result | Gross return in this example |
|---|---:|---|---:|
| AB | \$7.20 | Win | \$7.20 |
| AC | \$6.00 | Win | \$6.00 |
| AD | \$8.80 | Loss | \$0.00 |
| AE | \$6.40 | Loss | \$0.00 |
| BC | \$5.40 | Win | \$5.40 |
| BD | \$7.92 | Loss | \$0.00 |
| BE | \$5.76 | Loss | \$0.00 |
| CD | \$6.60 | Loss | \$0.00 |
| CE | \$4.80 | Loss | \$0.00 |
| DE | \$7.04 | Loss | \$0.00 |

The pairs ticket settles as follows:

- **Total stake:** 10 × \$2 = \$20.
- **Gross return:** \$7.20 + \$6.00 + \$5.40 = \$18.60.
- **Net result:** \$18.60 − \$20 = **−\$1.40**.

Three winning picks produce three winning pairs here, but their combined returns do not cover the cost of all 10 parlays.

## By 3s: which of the 10 triples win?

**Only ABC wins**, producing a gross return of **\$10.80**. Every other triple contains at least one losing pick.

ABC returns \$2 × 2.00 × 1.80 × 1.50 = **\$10.80**.

| Parlay | Potential gross return if it wins | Result | Gross return in this example |
|---|---:|---|---:|
| ABC | \$10.80 | Win | \$10.80 |
| ABD | \$15.84 | Loss | \$0.00 |
| ABE | \$11.52 | Loss | \$0.00 |
| ACD | \$13.20 | Loss | \$0.00 |
| ACE | \$9.60 | Loss | \$0.00 |
| ADE | \$14.08 | Loss | \$0.00 |
| BCD | \$11.88 | Loss | \$0.00 |
| BCE | \$8.64 | Loss | \$0.00 |
| BDE | \$12.67 | Loss | \$0.00 |
| CDE | \$10.56 | Loss | \$0.00 |

Potential returns are shown to the nearest cent. BDE’s potential return is rounded; because BDE loses, that rounding does not affect this example’s gross return.

The triples ticket settles as follows:

- **Total stake:** 10 × \$2 = \$20.
- **Gross return:** \$10.80.
- **Net result:** \$10.80 − \$20 = **−\$9.20**.

## What happens if you select both pairs and triples?

Selecting both sizes at **\$2 per parlay** puts **\$40 at risk**, returns **\$29.40 gross**, and leaves a **net loss of \$10.60**.

| Selected sizes | Parlays | Total stake | Gross return | Net result |
|---|---:|---:|---:|---:|
| Pairs only | 10 | \$20 | \$18.60 | −\$1.40 |
| Triples only | 10 | \$20 | \$10.80 | −\$9.20 |
| Pairs and triples | 20 | \$40 | \$29.40 | −\$10.60 |

The last row combines both sets: \$18.60 + \$10.80 = \$29.40 gross, then \$29.40 − \$40 = −\$10.60 net. The stake per parlay stays the same, but the number of paid parlays doubles. This is **not a comparison using the same total budget**.

## How can you check the example in the calculator?

The [ToolsGambling round robin calculator](https://toolsgambling.com/betting/round-robin-calculator) lets you check combination counts, total stakes, scenario payout ranges, and potential returns for individual parlays. **It does not let you mark individual picks as actual winners.** To reproduce the A/B/C result, manually select the relevant component returns from the `Pro` list and add them.

1. Click `+ Add selection` once to add a fifth selection to the four initial fields. Enter the decimal odds in A–E order: **2.00, 1.80, 1.50, 2.20, 1.60**. Rename the editable selection-name fields **A, B, C, D, E**, respectively.
2. Leave only `By 2s` selected. Deselect any other active sizes; each size button is an independent toggle.
3. Enter **2** in `Stake per parlay`.
4. Check for **10 combinations** and a **\$20 total stake**.
5. In `Pro`, find **A + B**, **A + C**, and **B + C**. Their potential returns are **\$7.20**, **\$6.00**, and **\$5.40**. For the scenario where only A, B, and C win, manually identify these winning components and add their returns: **\$18.60**. `Pro` shows potential returns; it does not determine which selections won.
6. Deselect `By 2s`, then select `By 3s`, keeping `Stake per parlay` at **2**. If you leave `By 2s` selected, both sizes remain active.
7. Check for **10 combinations** and a **\$20 total stake**. For the same scenario, manually count only the return for **A + B + C**: **\$10.80**.

The calculator also shows a payout range for a given number of winning picks. Its verified three-win payout bands for these inputs are:

| Combination size | Scenario payout range with three winning picks | Gross return when A, B, and C win |
|---|---:|---:|
| Pairs | \$15.96–\$23.92 | \$18.60 |
| Triples | \$8.64–\$15.84 | \$10.80 |

**The payout range does not identify A, B, and C as the winners.** It covers different possible sets of three winning picks. It is neither a probability interval nor an expected return: even with the same number of winners, the payout changes depending on which picks win and their odds.

## How do you avoid confusing stake per parlay with total stake?

Before confirming a sportsbook ticket, check whether its stake entry means **the amount per parlay or the total amount split across the parlays**. Operator stake-entry conventions vary.

In this example, \$2 funds **each** of the 10 component parlays, not the entire ticket. The bet365 example uses a per-parlay amount. Keep that distinct from the total stake: selecting both two-pick and three-pick parlays at \$2 each costs \$40 overall.

Inspect the accepted bet slip and reconcile three numbers: the combination count, stake per parlay, and total stake. For either the pairs-only or triples-only ticket here, the check is **10 × \$2 = \$20**.

For other combination structures, see the [broader guide to system bets](https://toolsgambling.com/blog/what-is-a-system-bet-explained).

## FAQ

### Can I include related picks in a round robin?

Do not assume every related pick can be combined. This example uses compatible picks; check the sportsbook’s rules to see whether your specific combinations are allowed.

### What changes if a pick is voided or a bonus applies?

This calculation does not cover those conditions. Check the sportsbook’s settlement rules, bonus terms, payout limits, and rounding rules before calculating the return.

### Does this round robin include straight bets?

No. This example includes only two-pick and three-pick parlays. Named system bets may include other combination sizes or straight bets, but that is a different ticket structure.