← Blog · 📝 Article · 19 October 2026

Betfair Tick Sizes: The Full Price Ladder and What a Tick Is Worth

Betfair Tick Sizes: The Full Price Ladder and What a Tick Is Worth

Betfair Exchange prices sit on a fixed ladder, and the gap between one price and the next (the tick) grows as the odds get bigger. It is 0.01 at the bottom and 10.0 at the top. You cannot back or lay at 3.14. You can only use a price that exists on the ladder, and a tick at 1.50 is worth very different money from a tick at 20.0.

Below you get the full ladder, the maths of what one tick costs a layer, and the mistakes that trip up beginners and anyone connecting trading software.

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TL;DR

Table of Contents

The Betfair price ladder in full

The ladder has ten bands. The increment is constant inside a band and widens at each threshold. The figures below match the published band structure on Trinity Logic’s price ladder page and on Statometrics’ tick size guide.

Price band Tick size Prices in the band
1.01 to 2.00 0.01 100
2.00 to 3.00 0.02 50
3.00 to 4.00 0.05 20
4.00 to 6.00 0.1 20
6.00 to 10.00 0.2 20
10.00 to 20.00 0.5 20
20.00 to 30.00 1.0 10
30.00 to 50.00 2.0 10
50.00 to 100.00 5.0 10
100.00 to 1000.00 10.0 90

A few practical points:

Why the steps get wider

The ladder is built so each step is roughly a similar-sized move in probability terms, not in price terms. A move from 1.01 to 1.02 and a move from 100 to 110 are both single ticks, yet they describe very different changes in the market’s view. That is why traders talk about ticks but think in probability.

What one tick is actually worth

What one tick is actually worth — overview diagram

A tick is a unit of price, not a unit of money. Statometrics makes this point well: experienced traders convert ticks into implied probability and profit before deciding anything, because the same tick has very different consequences at 1.50 and at 20.0.

Here is the implied probability maths for one tick up from a few prices. Implied probability is simply 1 divided by the decimal price. If you want the full treatment of that idea and the margin trap, read our piece on implied probability for bettors.

Move Implied probability before After Shift
1.01 to 1.02 99.01% 98.04% 0.97 points
2.00 to 2.02 50.00% 49.50% 0.50 points
5.0 to 5.1 20.00% 19.61% 0.39 points
10.0 to 10.5 10.00% 9.52% 0.48 points
20 to 21 5.00% 4.76% 0.24 points

The numbers are our own arithmetic from the formula above. The lesson is that a tick at the very bottom of the ladder is a large probability move, while at long prices a tick is a bigger percentage change of the price but a small change in probability.

What a tick costs a layer

What a tick costs a layer — overview diagram

When you lay, you act as the bookmaker. If you lay a horse and it wins, you pay out. Your liability is the backer’s stake multiplied by the price minus 1. That is why the price you accept matters so much.

Take a backer’s stake of £10:

Lay price Liability Next tick up Liability Extra risk per tick
2.00 £10.00 2.02 £10.20 £0.20
3.00 £20.00 3.05 £20.50 £0.50
5.0 £40.00 5.1 £41.00 £1.00
10.0 £90.00 10.5 £95.00 £5.00
20 £190.00 21 £200.00 £10.00

Two things follow. First, the extra risk per tick climbs quickly as prices lengthen, so being one or two ticks off at 20 costs far more than at 3. Second, the reward for laying is the backer’s stake whichever tick you take, so a worse tick raises your risk without raising your possible win. Laying a tick lower, when the market allows it, improves the ratio of risk to reward.

The same logic on a back bet

Backing works the other way round: a higher price is better for you. If you want to understand how the numbers hang together, our lay betting calculator shows liability, profit and break-even for any price you type in. Always check it against a valid ladder price.

Why liability should drive your stake

Because a tick changes your risk, the sound approach is to decide the loss you can accept first, then work backwards to a stake. Our guides on fixed liability staking and capping lay losses at 1 to 2% explain this in detail, and Betfair lay liability explained covers how the exchange reserves the money.

A simple example. You cap each lay at £20 liability.

The maths is ours. Each tick shrinks the stake you can offer, which in turn shrinks the potential win. This is why chasing a slightly longer price is not free when you are laying.

Minimum stakes and what a tick does to small bets

Since 7 February 2022, the minimum stake on the Betfair Exchange is £1.00. The same announcement notes that Starting Price bets carry a £10.00 minimum liability to qualify for reconciliation at the off.

At a £1 stake a tick is small money, but the percentages do not change. Commission also shapes how much of a tick you keep, which is why we suggest reading how Betfair commission impacts your profit before you judge whether a one-tick edge is worth chasing. For heavy winners, the Betfair Expert Fee is a separate consideration.

Invalid odds: the error that catches beginners

If you try to place a bet at a price that is not on the ladder, it fails. A price like 3.14 is not valid, so it must be rounded to a real tick, as Trinity Logic explains. The same rule applies through the API. Developers on the Betfair developer forum describe the INVALID_ODDS error as commonly caused by too many decimal places or a price that does not match the bands, and recommend validating every order price against the increments before sending it.

A quick checklist if you are using software:

  1. Round to the correct band, not to two decimal places.
  2. When you step a price by “two ticks”, move along the ladder, not by adding 0.02.
  3. Re-check after crossing a band boundary, such as 2.00 or 10.00.
  4. Keep the ladder in one place in your code so it cannot drift.

Odd prices in your data

If you analyse traded volume data, you may spot prices that are not on the ladder. Practitioners on the developer forum say these show up mainly in horse racing and usually result from cross-matching or Rule 4 reductions after a withdrawal. They are real matched trades, not errors in your parsing.

One more developer tip: in market data feeds, a size of 0 means money has been removed at that price, not that a zero-stake bet was placed.

Using ticks in lay betting on horses

Ticks matter at two moments: when you choose the price to lay at, and when you decide whether a signal is still worth taking after the market moves.

If you are new to the exchange, three pre-bet checks for betting exchange beginners is a sensible starting point, and lay betting explained simply covers the basics of betting against a horse.

Our view on ticks

We build lay signals for UK, Australian and US horse racing, so we think about ticks every day. Here is our honest position.

First, a tick is never neutral to a layer. At short prices the cost of being a tick or two out is small. At 15 or 20 it is not. That is why we publish every signal before the race, with the price it was found at, so you can see what you would have faced.

Second, strike rate means little without price. A high strike rate on short-priced selections can still lose money if the occasional loser is expensive. We track results by units and P&L, not just winners and losers, and we show losses. It happens. Transparency is the whole point.

Third, discipline beats cleverness. Set maximum liability before you look at the ladder, use the same rule every day, and treat tick-level improvements as a bonus. Our guide to a daily lay strategy walks through that process.

— Donkey

Using DonkeyRadar with the ladder

DonkeyRadar has a free tier with daily lay signals, and Pro is £29 per month after a seven-day trial. Pro adds real-time alerts by email and Telegram, the full results history and API access for trading software. The dashboard links straight to the Betfair Exchange market, and signals carry a staking tier grade so you can size against your liability cap. If you connect software, remember the ladder rules above: validate every price before you send it.

Look at the plans on DonkeyRadar, or read how we approach the numbers in our data-driven lay betting strategy. You can also see how the signals have done in our horse racing lay tips guide. Betting is for over 18s only, and you should never stake money you cannot afford to lose.

FAQ

What is a tick on Betfair?

A tick is the smallest price step allowed at a given point on the ladder. It is 0.01 between 1.01 and 2.00 and widens to 10.0 between 100 and 1000. Every valid price is one of these steps.

Are Betfair tick sizes the same at every price?

No. There are ten bands, and the increment gets larger as the odds get bigger. A tick at 1.50 is worth far less in money than a tick at 20, and it also moves implied probability by a different amount.

Why was my bet rejected as invalid odds?

The price was probably not on the ladder, for example 3.14 or a price with too many decimals. Round it to the nearest valid tick before you submit it. This applies to manual entry and to API orders alike.

What is the smallest bet you can place on the Betfair Exchange?

The minimum stake is £1.00, in place since 7 February 2022. Starting Price bets need a minimum liability of £10.00 to be reconciled at the off.

Does the tick size affect lay liability?

Yes. Liability is the backer’s stake times the price minus 1, so each tick up raises your risk. At a £10 backer’s stake, moving from 10.0 to 10.5 adds £5.00 to your liability.

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