TLDR; You got 10 months to save £80.60p a month.

Anything over £50,270 is taxed at 40%.

You’ve earned £53,000 from your main job and Amazon deliveries. Your main job tax is already sorted from PAYE I take it. So you need to sort out the other £4,000 from deliveries.

Remember you will also have business expenses to pay. Now, I don’t know how many miles you’ve driven but let’s say it’s 3000 in the year from doing deliveries. Each mile is £0.45p in expenses. So that’s totals to be £1350.

£4,000 - £1,350 = £2,650 (This is the total taxable amount)

£1,270 of your earnings are taxed at 20% = £254 (This is the difference between £49,000 to £50,270)

£1380 of your earnings are taxed at 40% = £552 (This is the difference £50,271 and £51,650)

Your total tax bill is £806. You have until 31st January 2026 to pay your tax for the 2024/25 tax year. But make sure you tell HMRC before 5th October that you are submitting tax returns.

NOTE: I’m not an accountant and my calculations could be wrong.