Tricast Bet and Forecast Bets Explained: Lines, CSF and CT

A forecast asks you to name the first two home, in the right order. A tricast bet asks for the first three, in order. Both are single-race bets, which sets them apart from the doubles and full-cover bets elsewhere in this section, and both are hard to win, which is why they can pay well.

The other thing that sets them apart is how they are paid. You don’t get a price for a forecast when you place it. The bet is settled on a dividend that is worked out after the race.

The forecast bet, straight and reversed

A straight forecast is a single bet: horse A to win and horse B to finish second. If B wins and A is second, the bet loses. Order matters.

A reverse forecast removes that problem by placing two straight forecasts: A then B, and B then A. It costs two stakes, and if your two horses fill the first two places in either order, one of the two lines wins. A £1 reverse forecast is £2 staked.

The reverse forecast suits a race where two horses look clearly better than the rest but there is little between them. If you have a firm view on which of the two wins, the straight forecast says so for half the stake. If you don’t, the reverse forecast pays for that doubt with a second line, and it is the cheapest way to cover it.

Forecast bets are accepted in races with three or more runners, according to the published rules of the firms checked for this page. With two runners, the forecast would simply be a win bet on one of them.

Combination forecasts

A combination forecast takes three or more horses and backs every possible pairing in every order. The number of lines is the number of horses multiplied by one less than that number. Three horses give 3 × 2 = 6 bets. Four horses give 4 × 3 = 12. Five horses give 20.

So a £1 combination forecast on four horses is £12. If any two of your four fill the first two places, in any order, one of the twelve lines wins. The other eleven lose. Only one line in a combination forecast can ever win, because only one horse can finish first and one second.

That last point is the one to keep in mind when the numbers look attractive. More horses in a combination forecast make it more likely that you will have the right pair, but the stake grows fast, and the return is always one line’s worth.

The tricast bet, straight and combination

A straight tricast is one bet on the first three in order: A first, B second, C third.

A combination tricast covers every order of the horses you choose. The count is the number of horses times one less, times two less. Three horses give 3 × 2 × 1 = 6 bets, the six possible orders of three. Four horses give 4 × 3 × 2 = 24 bets. Five horses give 60.

Like the combination forecast, a combination tricast can only ever have one winning line, because only one order of finish actually happens. A 50p combination tricast on four horses costs £12, and if three of the four fill the first three places, one of its 24 lines pays.

A tricast bet isn’t offered on every race. It is settled on the official computer tricast dividend, and the published rules of the firms checked for this page say that dividend is declared in handicaps with at least eight horses declared and at least six running. Some firms will settle a tricast as a forecast if the field shrinks below the level for a tricast dividend. As ever, the firm’s own rules decide.

How the CSF and CT are worked out

Bookmakers don’t set their own forecast prices. They use two industry dividends: the computer straight forecast, or CSF, and the computer tricast, or CT. Both are calculated after the race by a formula that starts from the starting prices of the horses involved and takes account of the size of the field. Both are declared to a £1 stake and printed in the official results.

That has a practical effect. You can’t know in advance what a forecast will pay, only roughly what kind of number to expect. A forecast involving two well-backed horses will pay a small dividend. One involving two outsiders can pay a very large one.

The settlement itself is simple. Your return is the dividend multiplied by your line stake, for the one line that won. Suppose, for illustration, that a race returns a CSF of £23.40 to a £1 stake. A 50p straight forecast on the right pair in the right order returns £11.70. A 50p reverse forecast, which cost £1, returns the same £11.70, because only one of its two lines wins. A 50p combination forecast on four horses, which cost £6, also returns £11.70. The dividend here is invented for the example; the arithmetic is not.

A tricast bet worked through

Take a handicap with a big field and four horses you think can fill the frame. A straight tricast on your preferred order costs a single line stake. A combination tricast on all four covers every order, 24 lines, and at 50p a line that is £12.

Suppose, again for illustration, that three of your four finish first, second and third, and the race returns a CT of £156.20 to a £1 stake. The winning line was staked at 50p, so it returns £78.10. The straight tricast would have returned the same £78.10 from 50p, if you had named the exact order. The combination tricast paid £12 for the insurance of not having to.

In the published results the two dividends appear together, usually as “CSF” and “CT” with a figure after each. They are always to a £1 stake, so scale them to your own line stake before you work out a return.

Why the finishing order is so hard to call

The difficulty of these bets is easy to put into numbers. In a ten-runner race there are 90 possible ways for the first two to finish, because any of the ten can win and any of the other nine can be second. There are 720 possible orders for the first three.

In a sixteen-runner handicap, those numbers are 240 forecast orders and 3,360 tricast orders. Most of those combinations are very unlikely, and the dividend reflects that, but it explains why a correct tricast in a big field can pay hundreds of times the stake.

It also explains why the combination bets have limits. Adding a horse to a combination tricast doesn’t just add a few lines; it multiplies them. The only defence is to be selective. A small number of horses you really believe in, in a race where the form points to them, is the whole method.

Forecasts and tricasts can’t be backed each way. They are already bets on placings, in a specific order, so there is no place part to add.

Forecasts on the tote: exacta and trifecta

The tote runs its own versions of these bets as pools. The exacta is the first two in the correct order. The trifecta is the first three in the correct order. Stakes go into a pool, a deduction is taken, and the remainder is shared among the winning tickets.

The two systems pay differently. The CSF and CT come from a formula based on the starting prices. The exacta and trifecta depend entirely on how much other people staked on the winning combination. On the same race, one can pay noticeably more than the other, and which is bigger isn’t predictable from the racecard. The Placepot page explains how tote pools and dividends work.

Non-runners and other rules

Rules on non-runners differ between firms, and forecasts are one of the areas where they differ most. One major firm’s published rules say a forecast with a non-runner in it is void, and a tricast with one non-runner stands as a straight forecast on the other two horses in the order given. A tricast with two non-runners is void. Other firms may do something different, and it is worth reading the rules of the one you use before a big field goes to post.

In a combination bet, a non-runner removes every line it appears in, and the bet continues on the other horses. A four-horse combination forecast with one non-runner becomes, in effect, a three-horse combination forecast.

When a forecast or tricast makes sense

These bets fit a particular kind of view. You don’t just think a horse will win; you have an opinion on how the race will be run and who will fill the places behind. That is most likely in races where you have studied the form closely, often big handicaps with plenty of runners, where the prices are big and the finishing order is genuinely uncertain.

The combination versions are a way of admitting that you know the likely principals but not the order. They are expensive for what they are, because only one line can win, so keep the number of horses small. Four horses in a combination tricast bet is 24 lines. Six would be 120, which is the same number of lines as a Super Heinz, spent on a single race.

A last aside: none of this is unique to horses. Forecasts and tricasts are also offered on greyhound racing, and the counting of lines, the one-winning-line rule and the dividend settlement work in exactly the same way.