Handicaps are an important aspect of Horse Racing and the majority of the races in the UK are handicapped. The idea behind a handicap race is to allow horses of different abilities to compete on a level footing. Therefore if the handicaps were all correct, in theory all the horses would cross the finish line at the same time. Using this system the best horse doesn't necessarily win the race.

The handicap of each horse is determined by its' official rating. This is devised by a board of six people who give each horse a rating which relates to the horses' performance in previous races. A horses age also affects it's official and between ages three, four and five the official rating is adjusted on a scale known as "weight for age" with a five year old given a higher rating than a three year old. When a horse has finished the required amount of races and has obtained an official rating the horse can enter a handicap race. The official ratings of all horse are stored by Weatherby's, horse racings' administrators. When a horse has raced the ratings will be amended on a weekly basis. Sometimes trainers will try and exploit this by races their horse in quick succession to take advantage of the fact the horses' rating has yet to be changed. Therefore running in race with a lower rating than they should have.

When entering a handicap race a horse is required to carry a specific weight depending on their official rating. This is carried by means of lead bars that are added to the saddle. If during a race some weight drops out of the saddle the horse will be disqualified.

If you bet on a horse with the highest official rating you will be betting on the horse which is carrying the most weight as it is supposed to be the best horse in the race.

In the US the amount of weight carried by a horse will be assigned to each horse depending on the conditions set out by the racing secretary of the course.