On the SA tax return, the profit stated is for the year ending....in whichever tax return you are doing, ie for 2009-10 tax return, any year that ends in that year, say 31/07/09 will be included, but not anything after that between 01/08/09 and 05/04/10 - that will be included in the following year. Its only when you cease to trade that an adjustment will be made, although then again it does depend on what date you were to cease.
Having the year end the same as the tax year does make it simpler to manage and get your head round!
if you get a client who starts trading on 15th September for example just advise the client that it makes sense for them to have a shorter first year and to do the books from 15.09.10 to 05.04.11. It makes sense so that they do not get hit with overlap profits, ie getting taxed on the same profits in the first couple of years (you may want to refresh your studies reagrding opening years), but basically they will pay tax on the same profits and this cannot be relieved until either the business changes its year end or it ceases. And as Phil says it makes our lives simpler.
