HMRC Registration: What Happens After You Register
After You Register
Registering with HMRC as self-employed is the first step. Here is what happens next.
Within 10 Working Days
Your UTR Arrives
HMRC sends your Unique Taxpayer Reference (UTR) by post. This 10-digit number is your identifier for all HMRC interactions. Keep it safe — you will need it for every tax return.
If it has not arrived after 10 working days, call HMRC on 0300 200 3310.
Your Self Assessment Account Is Created
You can now access your Self Assessment through your HMRC online account (Government Gateway). This shows your tax position, upcoming deadlines, and allows you to file returns.
During Your First Year of Trading
Keep Records
From the moment you start trading, keep records of:
- All income received
- All business expenses (with receipts)
- Mileage logs
- Bank statements
These records will feed into your first tax return.
Set Aside Tax
Do not wait until January to think about tax. Set aside 25-30% of every payment you receive. A separate savings account labelled "tax" is the simplest approach.
Consider MTD Requirements
If your income will exceed £50,000, you will need MTD-compatible software from April 2026. Even below this threshold, digital records are best practice.
By 31 January After Your First Tax Year
File Your Self Assessment
Your first tax return covers from your start date to 5 April. If you started in September 2026, your first return covers September 2026 to April 2027 (filed by 31 January 2028).
Pay Your Tax Bill
Income tax, Class 2 NI, and Class 4 NI are all due by 31 January. If your bill exceeds £1,000, HMRC will also set up payments on account for the following year.
Ongoing Obligations
- File a Self Assessment return every year (even if you made a loss)
- Pay tax on time (31 January and 31 July)
- Keep records for at least five years after the filing deadline
- Register for VAT if your turnover exceeds £90,000
- Comply with MTD requirements when applicable
Set up Accounted as soon as you receive your UTR and start tracking from day one.
Registration is just the beginning. Get organised early. Sign up for Accounted and let Penny manage your tax journey from the start.
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