What Does SP Mean in Horse Racing? Starting Price, Early Prices, BOG and Betfair SP

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By The Guv'nor · Last updated October 2026

What does SP mean in horse racing? It's the starting price: the official odds a horse is returned at when the race starts. Don't ask for a price when you bet and you're paid at SP. In British racing it's taken from a sample of bookmakers' prices at the off, so you only know what you got once they're running.

Whether to take a price or wait for the SP is one of the few things in betting you fully control, so I've put a year of Betfair data against it below.

What does SP mean in horse racing? How the starting price is set

The Starting Price Regulatory Commission (SPRC), the independent body behind SPs in British racing, defines the starting price for each horse as "the market price at the off, offered by selected bookmakers in a sample", picked from firms whose each-way terms are closest to the usual ones.

That sample used to come from the betting ring. Not any more: the SPRC's own history says SPs moved to mainly off-course bookmakers' prices, with an element for the on-course market, from 1 May 2022, and the system was revised again in July 2024. As of 2026 its rules list nine SP-qualified bookmakers, a sample of normally at least six, and no SP at all if three bookmakers' prices can't be got.

How the SP is worked out: a worked example

Line up the sampled prices for a horse from longest to shortest, split the list into two equal halves, and the SP is the shortest price in the longer half. Here it is with made-up prices from an eight-bookmaker sample:

Two bookies were bigger than 9/2, but that's no help if you left it to SP. An SP Validator confirms the prices shortly after the off, and PA Sport sends them out to the media.

SP doesn't strip out the bookies' margin either. It's built from their prices, so the margin comes with it, and in the 2026 Grand National it sat heaviest on the outsiders. That race's SP book is broken down in value betting in horse racing.

Early prices vs SP: which way does the market move?

An early price is a fixed price you take before the race. Coral's horse racing rules, as one example, define it as a price taken after final declarations but before the first live or racecourse show.

Bookies don't publish their early prices in bulk, but Betfair publishes its exchange prices. So I ran every UK and Irish win market in Betfair's daily price files for races from 1 October 2025 to 30 September 2026: 12,991 races (10,086 UK, 2,905 Irish) and 118,584 runners with a morning price.

Table 1: how prices moved, grouped by the price at the off

Horses that ended up fancied had mostly been bigger in the morning: the typical one was about 11% bigger before 11am. Horses that ended up big outsiders had mostly been shorter, with the typical morning price about 31% shorter than the BSP. And the market as a whole drifts: 60.1% of runners were bigger at the off.

Table 2: the same runners, grouped by what you knew at 11am

Table 1 sorts horses by a price you don't have yet. This is the honest version, grouped by the morning price.

• Taking every morning price blind is worse than waiting. It returned −4.6% against −0.5% at BSP, because most horses drift. Of runners at 21.0 or bigger at 11am, 66.2% drifted further.
• An early price pays when you know something the morning market doesn't. It only beats the price at the off on the horses that went on to shorten, the ones in Table 1's left-hand column. Find those before the money arrives and the early price is worth having. Guess, and you're on the wrong side of the drift.
• The last column is why BOG matters. Being paid the bigger price turns a losing habit into a winning one on paper. It's only an illustration: nobody pays the bigger of two exchange prices, BOG pays a bookmaker SP with their margin in it, and the morning market is thin (a median £364 traded per runner before 11am against £10,206 before the off). Real BOG is worth far less than +13.3%, but it's worth something.

Best odds guaranteed: how BOG works and where it stops

Best odds guaranteed (BOG) means you take an early price, and if the SP comes back bigger, you're paid at the SP. In Coral's words, bets "will be settled at the Starting Price (SP) if the SP is bigger than the price originally taken".

Without BOG, that last line pays £70 on a drifter. That's the whole point of it.

The limits worth knowing

BOG is a bookmaker concession, not a racing rule, so every firm sets its own terms. Coral's published rules, as the example:

• Start time: online bets from 8am on the day, on all UK and Irish racing. Bets in the shop don't qualify unless stated.
• Opt-in: since 27 April 2026 you have to opt in, once, to get it.
• Exclusions: ante-post, Tote and pool bets, enhanced prices, betting without, place-only and match bets, in-running bets and bet builders, among others. An ante-post price gets no BOG.
• Cap: £10,000 per customer per day.
• Non-runners: they pay the bigger odds after any Rule 4 deduction. Sizes are in my Rule 4 deductions table.

Check whether your bookie's BOG covers multiples too. If you're putting my lucky 15 tips into one bet, find out before the first leg runs.

Betfair SP and the Tote: two other starting prices

How Betfair Starting Price works

BSP is the exchange's own price at the off. In Betfair's explanation, when the event starts it weighs the SP money from backers and layers against each other and any unmatched exchange bets. No profit margin is built in; Betfair charges commission on your net winnings instead.

That's why BSP is my yardstick. Backing every runner at BSP returned −0.5% before commission across those 118,584 runners, about as close to fair as betting gets.

The Tote is a pool, not a price

Everyone's Tote stakes go into one pool and, as The Jockey Club's Tote guide puts it, the total "will be shared amongst the punters with the winning tickets". The on-course screens show odds that change right up to the off. Fewer people on your horse means a bigger share if it wins.

So Tote vs SP has no fixed answer. The Tote can beat the SP on a horse the pool ignored and fall short on a popular one, and you don't know which until the pool closes.

Which price should you take?

1. Reason to think it'll be backed? Take the early price, with BOG. That's the Table 1 pattern, and BOG covers you if you're wrong.
2. Fancy an outsider? Don't leave it to bookmaker SP. Outsiders mostly drift and SP carries the margin. Take a price with BOG so you get the drift too, or compare with BSP.
3. No view on the price at all? Waiting costs little on average. Taking every morning price blind did worse than BSP.
4. Worried about non-runners? An SP bet only takes a Rule 4 if a horse is withdrawn and no new market is formed. A price you've taken is liable to Rule 4 too; Coral, for one, bases it on the withdrawn horse's price when you struck the bet.

New to prices? Start with horse racing odds explained and my beginner's guide to betting on horse racing, then the ten rules in my horse racing betting strategy guide.

Why my tips land in the morning

Look, I was a Quantitative Researcher at a Tier 1 investment bank, so I'm essentially a statistics/maths geek, and I don't judge a bet on whether it won. I judge it on the price and on profit month to month.

My premium tips go out in a morning newsletter, and Table 1 shows why that timing matters. A tip is only worth having if it finds a horse the market has got wrong, and if it's right, that horse tends to shorten. In the morning you can still get the price. When I have smart money or stable information to pass on, that's exactly the kind of horse you want to be on before everyone else.

I like outsiders and each-way value too, and outsiders mostly drift. That's where BOG earns its keep: if one drifts, you get the bigger SP. I bet on every horse I tip, and most of your favourite bookies won't take a bet from me, so if yours still gives you BOG, use it.

If the price has gone by the time you read it, don't chase it. Unsure about a bet? Skip it. Stake in points, and remember: understanding that losers are a thing is the key to being a winner longer term.

Starting price FAQs

What time does best odds guaranteed start?

Each bookie sets its own time. Coral, for example, offers BOG on online bets from 8am on race day on UK and Irish racing, as long as you've opted in, and in-running bets don't qualify.

Is Betfair SP bigger than the bookies' SP?

BSP has no margin built in and bookmaker SP does. In the 2026 Grand National all 34 runners went off bigger at BSP than at SP, with the biggest gaps on the outsiders (the case study is on my value betting page). That's one race, before commission, so compare after Betfair's cut.

What happens to an SP bet if a horse is withdrawn?

If yours is the non-runner, you get your stake back. If another horse comes out, an SP bet only takes a Rule 4 deduction when it's too late for a new market to be formed.

More in this guide

• How to bet on horse racing: the beginner's guide
• Horse racing odds explained, with a full odds chart
• Rule 4 deductions: the full table
• Each-way betting explained
• Why bookies restrict winning accounts