If you deferred paying your July 2020 payment on account, you will need to pay the deferred amount in addition to any 2019/20 balancing payment and first 2020/21 payment on account by 31 January 2021. This may be a larger payment than you usually pay in January.
If you're unable to pay this liability in full by 31 January 2021 then you can set up a Time to Pay payment plan of up to 12 months online. If your self-assessment tax debts are up to £30,000 then you'll able to access this Time to Pay facility through the gov.uk website and approval will be automatic and immediate.
If your self-assessment debts are over £30,000 or you need longer than 12 months to repay your debt in full then you will still be able to apply for a Time to Pay arrangement by calling HMRC. It is likely that you will have to provide evidence of the reason you can not pay and produce cash flow forecasts.
We are here to help so please contact us if you wish to discuss any of the above.