ISA allowance 19/20
For tax year 19/20, April 6th 2019 to April 5th 2020, the allowance which can be utilised across all ISA products (Stocks and Shares ISA, Cash ISA Innovative ISA and LISA) is £ 20,000.00. This remains unchanged from the previous tax year.
Within one tax year you may invest a total of £ 20,000.00 spread across all these products, but you may only invest in one of each type, so you cannot invest £ 10,000.00 in 2 Cash ISAs with different providers, but you could invest £ 10,000.00 in a Cash ISA with one provider and £ 10,000.00 in a Stocks and shares ISA with another manager.
Though investing in a LISA (Lifetime ISA account) will use part of your overall £ 20,000.00 ISA allowance, you may only invest a maximum of £ 4,000.00 in a LISA, e.g., you can invest £ 4,000.00 in a LISA, £ 10,000.00 in a Cash ISA and £ 6,000.00 in a Stocks and shares ISA.
JISA allowance 19/20
The JISA allowance for tax year 19/20 will be £ 4,368.00, which is an increase of £ 108.00 from 18/19 when the allowance was £ 4,260.00. The JISA allowance is entirely separate from the £ 20,000.00 overall ISA allowance. In the tax year the child turns 18, they can invest £ 4,368.00 in a JISA and £ 20,000.00 in adult ISA products, or combination of them. This is, of course, only possible in the tax year the child turns 18 and not possible at any other time.