Help! may have messed up my ISA allowance.

masonic

Then the £20k is the invalid one. It would be advisable to keep this money separate from your other ISA money while you wait to see what if anything HMRC will do.

FrugaiMacDugal

So your £17k 1 year fix is fine.

Your £20k 2 year fix is £17k oversubscribed, not sure if £3k still valid.

Lets say you are getting 5% interest, paid annually on anniversary of opening.

For first year you will get £850 interest added to the £17000, making £17850.

For the second year you will get £892.50 added, making £18742.50.

So £1742.50 total interest.

If your tax rate is 20% you will only owe £348.50, which could be collected through a tax code change.

This is all conjecture on my part, so will no doubt be corrected.

masonic

FrugaiMacDugal said:

So your £17k 1 year fix is fine.

Your £20k 2 year fix is £17k oversubscribed, not sure if £3k still valid.

 Would still have been a limit of subscribing to one cash ISA per tax year in 2023/24.

We should not assume there will be a tax charge, as that is uncommon for a first offence.