Understanding Starting Prices (SP)
The Starting Price, commonly abbreviated to SP, is the official price of a horse at the exact moment a race begins. It is one of the most important concepts in horse racing betting because it serves as the default settlement price for bets where no fixed odds were taken, and it is the benchmark against which all other odds are compared. Understanding how SP works, when it is advantageous to take SP rather than fixed odds, and how the Betfair SP differs from the traditional industry SP will help you make smarter betting decisions.
Best Odds Guaranteed (BOG) is an offer from most major UK bookmakers that gives you the best of your fixed price or the SP, whichever is higher. If you take 5/1 early and the horse starts at 8/1, you are paid at 8/1. If you take 5/1 and it starts at 3/1, you keep your 5/1. BOG effectively removes the downside risk of taking an early price and is one of the most valuable promotions available to horse racing bettors. Always check if your bookmaker offers BOG before taking a fixed price.
How the Starting Price Is Determined
The official industry Starting Price in British horse racing is determined by representatives of the Starting Price Regulatory Commission (SPRC). These officials attend every race meeting and stand in the on-course betting ring, observing the prices offered by the bookmakers at the moment the starter lets the field go. They record the odds available from a sufficient sample of on-course bookmakers and calculate a representative price for each horse.
The process is designed to reflect the genuine state of the on-course market at the time of the off. If most on-course bookmakers are offering 4/1 about a horse at the start, the SP will typically be recorded as 4/1. The SPRC looks at the general weight of prices rather than any single bookmaker's offering. This system has been in place for over a century and remains the standard settlement price for bets placed at SP through all bookmakers, whether on-course or online.
One important nuance is that the on-course market can differ significantly from the online market. On-course bookmakers react to the money being wagered in the ring, which can be influenced by large cash bets from racecourse attendees. Online bookmakers, meanwhile, are influenced by the much larger volume of bets placed through their websites and apps. This discrepancy means the official SP sometimes surprises punters who have been watching prices move online throughout the day.
SP vs Fixed Odds: Comparison Scenarios
The decision between taking a fixed price early and waiting for the SP is one of the most common dilemmas in horse racing betting. The table below illustrates six real-world scenarios showing when each approach produces better returns for a £10 stake.
| Scenario | Fixed Odds Taken | SP Returned | Fixed Return (£10) | SP Return (£10) | Better Option |
|---|---|---|---|---|---|
| Horse backed early, shortened | 5/1 | 3/1 | £60 | £40 | Fixed Odds |
| Horse drifted in market | 2/1 | 4/1 | £30 | £50 | SP |
| Morning favourite, well supported | 7/2 | 5/2 | £45 | £35 | Fixed Odds |
| Outsider with late money | 14/1 | 8/1 | £150 | £90 | Fixed Odds |
| Non-runner caused market shift | 6/1 | 9/1 | £70 | £100 | SP |
| Price unchanged from morning | 3/1 | 3/1 | £40 | £40 | Equal |
| BOG customer, horse drifted | 4/1 | 7/1 | £80 (BOG pays 7/1) | £80 | Fixed + BOG |
| BOG customer, horse shortened | 10/1 | 6/1 | £110 (keeps 10/1) | £70 | Fixed + BOG |
The Betfair Starting Price (BSP)
The Betfair Starting Price is an alternative to the traditional industry SP, calculated entirely from activity on the Betfair exchange. When a race goes off, Betfair takes all the unmatched back and lay bets in its exchange pool and uses an algorithm to determine a price that balances the interests of backers and layers. The result is often regarded as a more accurate reflection of true probability because it is derived from a much larger pool of money than the on-course market alone.
The BSP frequently differs from the industry SP, sometimes significantly. In races where the on-course market is thin — particularly at smaller meetings with fewer bookmakers — the BSP can be noticeably different. For heavily-backed favourites, the BSP and industry SP tend to align closely. For outsiders and in less popular races, the gap can widen. Some shrewd punters use BSP as a benchmark for identifying value in the fixed-odds market. If a horse's fixed price is significantly larger than its likely BSP, that may represent a value opportunity.
When to Take SP vs Fixed Odds
The decision depends on your view of how the market will move. If you believe a horse is likely to attract support and its price will shorten, take the fixed price early to lock in value before the market moves against you. Horses that have won their latest start, or are trained by in-form trainers at courses they handle well, often shorten as the race approaches.
Conversely, if you think a horse might drift — perhaps because it is not the obvious form pick, or the ground might not be perfect — taking SP could yield better returns. There are also situations where you simply cannot watch the market and need a price. In those cases, if your bookmaker offers Best Odds Guaranteed, always take the fixed price because BOG ensures you cannot lose out either way. You will receive whichever is higher: your fixed price or the SP.
Best Odds Guaranteed Explained
Best Odds Guaranteed is a promotion offered by most major UK bookmakers that eliminates the guesswork around SP versus fixed odds. When you take a fixed price on a UK or Irish horse race, and the SP returns higher, the bookmaker automatically pays you at the SP instead. If the SP is lower than your fixed price, you keep the fixed price. In either case, you receive the best possible outcome.
BOG terms vary between bookmakers. Some restrict it to bets placed on the day of the race, while others extend it to prices taken the evening before. Certain bookmakers exclude specific meetings or cap the maximum extra payout from BOG. A few apply it only to win bets and not to the place part of each way bets. Reading the terms and conditions of your bookmaker's BOG offer is essential before relying on it as part of your strategy. When BOG is available without restrictions, it represents one of the best value promotions in the industry — effectively giving you a free option on market movement.