Novice Isa question

NotRichAtAll

So i am new to isa's and opened my first in june 2025 i put 15k in one and 5k in another. Now when it comes to been able to deposit more money in them my question is this:- if i put another 20k into the 15k isa do i get interest on 35k or just the new 20k?

thanks, please don't crucify me :)

wmb194

https://forums.moneysavingexpert.com/discussion/6659028/novice-isa-question

Assuming the account allows additional deposits and depending on its T&Cs you'll usually earn interest on the whole amount but when are you thinking of doing this? It sounds like you've used your £20k allowance for the 2025/26 tax year (06/04/25 to 05/04/26).

eskbanker

https://forums.moneysavingexpert.com/discussion/6659028/novice-isa-question

If you've contributed your full £20K annual allowance for 2025/26 then you can't pay any new money in until after 6 April, but once you do, the full balance will continue to earn interest.

NotRichAtAll

Thanks for the replies, yes i am thinking after 6th april 2026 for the next deposit