ISA investment limits
Every UK resident over the age of 16 has an ISA allowance. The current ISA investment limit is £10,200 (2010 - 2011 tax year) per tax year. All £10,200 can be put into a stocks and shares ISA. Alternaitvely a maximum of £5,100 can be held in a cash ISA, with the remainder (£5,100) going into a stocks and shares ISA. Only UK residents over 18 may invest in a stocks and shares ISA, so the ISA allowance is only £5,100 per year for 16 and 17 year olds.
The ISA investment limit is the maximum that any person can invest in a given tax year. If you have not used your allowance by the end of the tax year (April 6th) then the allowance is lost forever. Once the annual investment limit has been reached for the cash component, the equities component or the total combined, more cannot be paid into that years ISA allowance.
If you withdraw money from your ISA(s) then the allowance is 'used'. For example, if you deposit £5,100 in a cash ISA, and withdraw £200, you cannot add that £200 back into the account. You are deemed to have used your annual ISA allowance even though the ISA holding is below the annual limit. If you had originally only deposited £4,900 into the cash ISA, then you would be permitted to top-up by £200 in the same year to reach your allowance.
Investors can either hold all of their annual ISA investments with one provider, or can have different providers for the cash and equities portions of the ISA. You can hold previous years deposits and investments with different providers to the current year.
In 2009-2010 the ISA investment limit was £7,200 (£3,600 in cash, £3,600 in stocks and shares). Savers over the age of 50 had an increased allowance of £10,200, but this was increased for everybody this year (see ISA age rules for more information). There are no extra allowances for the 2010 - 2011 tax year. The old scheme of mini and maxi ISAs no longer exist, having been scrapped in 2008. There is no overall maximum investment limit - so keep using your yearly allowance!