From your account dashboard, select your account. Your current interest rate then shows among your account details. (If you’re on the app, it’s beneath your available balance, and if you’re on the website, it’s under your sort code.)
You can add a bonus rate to your Online Savings Account or Cash ISA at any time, as long as there’s one available.
From here, you’ll be able to renew your bonus to the current available rate. If you do this before your current bonus rate expires, your current bonus rate will come to an end and you’ll start earning interest at the new bonus rate immediately, for 12 months from that day.