HMRC announced on Friday, 19 February that Self-Assessment customers will now not be charged the initial 5% late payment penalty, if they pay their tax or make a Time to Pay arrangement by 1 April, 2021.

The deadline has not changed, but this year, because of the impact of COVID 19, HMRC is giving taxpayers more time to pay or set up a payment plan.
Anyone worried about paying their tax should contact HMRC for help and support on 0300 200 3822, to discuss taking advantage of the self-serve Time to Pay facility, which also allows customers to spread the cost of their tax liabilities into monthly instalments until January 2022.
Customers can then set up a payment plan online, on GOV.UK.
The payment deadline for Self-Assessment was 31 January 2021, and interest is already being charged from 1 February on any amounts outstanding
Your payment plans, or payments in full must be in place by midnight on 1 April to avoid a late payment penalty
Meantime, Self-Assessment customers who have yet to file their tax return should do so by 28 February 2021 to avoid a late filing penalty.