Can I open a Lifetime ISA if I already have an ISA?

Under existing ISA rules, you can pay into one of each type of ISA per tax year (e.g. a Cash ISA, a Stocks & Shares ISA and a Lifetime ISA). For the 2020/21 tax year, the annual contribution limit for the Lifetime ISA is £4,000 per tax year – this counts towards the overall annual ISA contribution limit of £20,000.