The easy answer you’ve probably come for? As of 2018, the ISA limit is* *£20,000 per year per person. The yearly limit for a Lifetime ISA is £4,000, to which the government will add a 25% bonus of up to £1,000. This £4,000 counts towards your annual £20,000 limit. If you want to open a Junior ISA for your child under 18, as of 2018, you’re free to deposit £4,128 per year, which does not count towards your overall £20,000 per year limit.