'SP' means Starting Price and is the final price or last traded price on an event before it begins. For football betting, that would be the last price before a match goes in-play and in horse racing, the last price that is traded before a race starts. 

How is the SP decided?

The forming of the SP predominantly relates to horse racing and greyhound racing. Under current circumstances when neither bookmakers nor customers are present on a racecourse (due to the coronavirus pandemic), a sample of all the odds from highest to lowest is collected from 12 leading off-course bookmakers. That list is then divided in two and the SP is formed from the shortest odds that are available in the sample with the longest odds.

When bookmakers are permitted on racecourses, the same theory applies however the sample of the odds is collected from on-course bookmakers whose terms most closely reflect that of the off-course bookmakers. 

When would you use SP?

Traditional bookmakers, particularly when it comes to horse racing, will offer you the option of accepting the current odds or accepting the SP. If you were to accept the SP, you do so in the knowledge that the price may fluctuate, therefore possibly offering higher or lower odds prior to the event starting.

 How is the Smarkets SP different?

The SP on Smarkets is slightly different to the normal or 'industry' SP as we calculate it ourselves.

It is calculated based on the volume of back and lay bets in the relevant market and as such provides a more accurate representation. It is also almost always a better price in comparison with the industry SP.