I'll confirm the 5% plus back up the other 95%.
Spreadbetting is just that (under current U.K tax law), tax exempt, that is, income and capital gains.
I've spreadbetted for over 4 years and you need not pay anything.
BUT:
Be aware, because it is gambling and not an income (however you see it) it is not taxable you will find it extremely difficult if not impossible to borrow any such somes as a mortgage without having to lay down huge deposits and going self cert which incurs penalties on interest a long with other such penalties.
Banks dont lend to gamblers as a general rule so unless you have your current situation backed up with an income you may find your current mortgage in jeopardy (although they generally dont mind providing you keep up repayments).
This next bit is the part most people find difficult to understand or confusing:
If you are spreadbetting for a living then winnings is all they are. The losses you cannot tax deduct the same as you cannot be tax deducted for your wins.
The only time gambling is taxed is if you are a professional - this means (not a professional trader) but as a business that trades to show proof of system ect, you can then off set your losses against your gains including all other expenses with the idea that you take profit from paying customers.
If trading (betting) for yourself then you need not worry but always check with your current lenders as this could prove a problem should you wish to re-mortgage or get a loan or even HP on a car.
