A company dividend essentially transfers money to its shareholders. This causes its share price to drop on a specific date, along with the index it is part of. As a lot of spread bettors bet on the FTSE 100 and FTSE 100 companies pay dividends you need to bear this in mind, as your broker will adjust the FTSE100 spread bet price each time.
Different brokers apply at different times, always on a Wednesday after the close each week.
This website provides the dividend amounts for each week, and Reuters and other news sites also publish it.
Example
Say you are holding a £5 per point short on the FTSE daily cash contract and the dividend is 24.7
It will be 24.7 times your £5 so £123.50 will be debited from your account if you are holding a short. IG (the most popular broker) apply it at 4:30pm, others at 9pm. This doesn’t apply if you are holding a futures contracts, only a daily cash bet.
If you hold a long over the dividend then the amount is credited to your account. The FTSE quoted price is adjusted down though, so your position will reflect the same amount either positive or negative.