How to Use HMRC's Online Services — A Complete Walkthrough

The Accounted Business Team·10 March 2026·9 min read

Getting Started with HMRC Online Services

HMRC's online services are where you manage most of your tax affairs as a self-employed person in the UK. From filing your Self Assessment return to checking your National Insurance record, almost everything happens through these digital services.

The problem? HMRC's website isn't exactly known for its intuitive design. It's functional, but navigating it for the first time (or even the fifth time) can feel like wandering through a government labyrinth. Things are in unexpected places, the terminology is confusing, and error messages sometimes read like they were written in code.

This guide walks you through everything step by step — setting up your account, finding the important sections, and dealing with the common issues that trip people up.

Creating a Government Gateway Account

Government Gateway is the login system HMRC uses for all its online services. Think of it as your key to everything tax-related online. If you don't already have an account, here's how to create one.

Step 1: Visit the Sign-In Page

Go to gov.uk and search for "HMRC sign in" or navigate directly to the Government Gateway sign-in page. Click "Create sign in details."

Step 2: Provide Your Details

You'll need:

An email address
A mobile phone number (for security codes)
Your full name

HMRC will send you a verification email and an SMS code. Enter both to continue.

Step 3: Your User ID

Once verified, HMRC generates your Government Gateway User ID. This is a 12-digit number. Write it down and keep it somewhere safe. Unlike most modern services, you can't use your email address to log in — you need this specific ID.

Losing your Government Gateway User ID is one of the most common issues people face. Save it in a password manager.

Step 4: Set Your Password

Create a strong password. HMRC has specific requirements (minimum 8-12 characters, mix of letters and numbers). Again, save this in a password manager.

Step 5: Verify Your Identity

HMRC needs to confirm you are who you say you are. You'll answer questions based on information HMRC already holds about you. This might include:

Details from a recent payslip or P60
Information from your tax credit claim
Details from your passport or driving licence
Your National Insurance number

If you can't complete identity verification online, you can request a verification letter by post (which takes about 7 working days) or call HMRC.

Step 6: Enrol for Self Assessment

Once your account is created and verified, you need to "enrol" for the services you want to use. For most sole traders, this means Self Assessment. Navigate to "Add a tax" and select Self Assessment to link it to your account.

If you've already registered for Self Assessment and have a UTR number, you'll enter it here. If you haven't registered yet, you'll need to do that first — see our step-by-step registration guide.

Navigating the Dashboard

Once you're logged in, you'll see your Personal Tax Account dashboard. It looks sparse, but it contains links to the key areas.

The Main Sections

Self Assessment — Where you file your tax return, check your balance, and make payments. This is where most sole traders spend their time.

PAYE — If you're employed alongside being self-employed, your PAYE information (tax code, employer details) appears here. Useful for checking that your tax code is correct.

National Insurance — View your NI record, check for gaps, and see your qualifying years for State Pension.

Messages — HMRC correspondence appears here. Check this regularly — important notices sometimes go to your online messages rather than (or in addition to) a paper letter.

Tax Code — View and, in some cases, update your tax code if your circumstances change.

The Self Assessment Section

This is the most important part for sole traders. Here's what you'll find and how to use it.

Filing Your Tax Return

When it's time to file, you'll see a link to start or continue your Self Assessment return. The online filing process walks you through various sections:

Personal details — Confirm your name, address, and date of birth
Employment income — If you have employment alongside self-employment
Self-employment — Your business income and expenses
Other income — Savings interest, dividends, rental income, etc.
Tax reliefs — Pension contributions, Gift Aid, etc.
Summary — Review everything before submitting

The self-employment section asks for your total income and total expenses. You don't need to list every individual transaction — just the totals by category. This is where keeping good records throughout the year (using software like Accounted, for example) makes filing dramatically easier. If Penny the AI bookkeeper has been categorising your expenses all year, you simply transfer the totals.

Viewing Your Tax Calculation

After submitting your return, HMRC generates a tax calculation showing:

Your total income
Your personal allowance (£12,570 in 2025/26)
Income Tax due (20% on £12,571–£50,270, 40% on £50,271–£125,140, 45% above £125,140)
National Insurance due (Class 2 at £3.45/week, Class 4 at 6%/2%)
Any payments on account for the following year
Total amount due and payment deadlines

Checking Your Balance

The "View your account" or "Check what you owe" section shows your current Self Assessment balance. This includes:

Tax due from your most recent return
Payments on account (advance payments towards next year's bill)
Any penalties or interest charged
Payments you've already made

This is also available through the HMRC app, which can be quicker for a simple balance check.

Making Payments

HMRC offers several ways to pay your Self Assessment bill.

Direct Online Payment

From the Self Assessment section, click "Make a payment" to pay by:

Debit card (no personal credit cards)
Direct bank transfer
Through your online banking

Setting Up a Direct Debit

You can set up a direct debit to pay future Self Assessment bills automatically. This is particularly useful for payments on account, which have fixed dates (31 January and 31 July). To set one up:

Go to "Set up a Direct Debit" in the payments section
Enter your bank details
Choose whether to pay the full amount or specific bills
Confirm and submit

A direct debit means you'll never accidentally miss a payment deadline. Given that late payment penalties can add up, this peace of mind is worth having.

HMRC Payment Reference

When paying by bank transfer, you'll need HMRC's bank details and your payment reference. Your reference is your 10-digit UTR followed by the letter "K." Getting this wrong is one of the most common payment issues — HMRC can't allocate your payment to your account if the reference is incorrect.

Time to Pay

If you can't afford to pay your bill in full, HMRC offers "Time to Pay" arrangements. You can set these up online if your bill is under £30,000 and you're within 60 days of the payment deadline.

Requesting a UTR

If you're registering for Self Assessment for the first time, you'll need a Unique Taxpayer Reference. Register as self-employed through the HMRC website, and HMRC will send your UTR by post within 10-21 working days. Once you have it, add it to your Government Gateway account. Your UTR stays with you for life — don't confuse it with your National Insurance number.

Checking NI Contributions

Your National Insurance record is important for your State Pension entitlement. To check it:

Navigate to "National Insurance" from your dashboard
View your record year by year
Check for any gaps or incomplete years

As a sole trader, you pay:

Class 2 NI: £3.45 per week (contributes to your State Pension)
Class 4 NI: 6% on profits between £12,570 and £50,270, then 2% above £50,270

If you have gaps in your record, you may be able to make voluntary contributions to fill them. This can be worth doing if it means qualifying for additional State Pension years.

Accessing Correspondence

HMRC increasingly sends important documents to your online account rather than by post. Check the "Messages" section regularly for:

Tax calculations and statements
Coding notices
Payment reminders
Penalty notices
General correspondence

Some messages have a deadline for responding. Don't let them pile up unread.

Common Error Messages and What They Mean

"We could not verify your identity"

Your answers to the verification questions don't match HMRC's records. Double-check your details are exactly right. If you've recently moved, changed jobs, or had other changes, your records might not be updated yet. Try a different verification method or call HMRC.

"Your enrolment is pending"

After enrolling for Self Assessment, there's a waiting period while HMRC activates your access. This can take a few days. If it's been more than 7 days, contact HMRC.

"Your return has not been received"

This usually means the submission didn't complete properly. Go back to the filing section and check whether your return shows as "Submitted" or "In progress." If it's still in progress, complete the remaining sections and resubmit.

"Payment not allocated"

Your payment was received but HMRC can't match it to your account. This almost always means the payment reference was wrong. Call HMRC with your payment details, and they can allocate it manually. This is frustrating but fixable.

"This service is unavailable"

HMRC's systems go down for maintenance, usually at weekends and during off-peak hours. They also experience heavy traffic around deadlines (particularly late January). If you see this, wait and try again later.

"You need to complete your return before you can view your calculation"

Self-explanatory, but it trips people up. Your tax calculation only appears after you've submitted your return, not while it's in draft.

Tips for a Smoother Experience

Use a desktop computer for filing your return — The mobile experience is poor for detailed forms
Save your progress regularly — The system can time out after inactivity
Keep your Government Gateway details in a password manager — You will forget them otherwise
File well before the deadline — The system slows dramatically in late January
Screenshot your submission confirmation — Proof of filing is important
Check your messages monthly — Don't wait for a postal letter
Use MTD-compatible software for record-keeping — It makes the filing process dramatically easier when your figures are already organised

The Bottom Line

HMRC's online services are essential for every sole trader. They're not the most user-friendly government portal you'll ever use, but once you know where everything is, they're manageable.

The key is getting set up properly — Government Gateway account, identity verification, Self Assessment enrolment — and then checking in regularly rather than leaving everything until January.

For the day-to-day record-keeping that feeds into your Self Assessment return, using software like Accounted means your figures are ready to go when it's time to file. Penny keeps everything organised so you're not scrambling to reconstruct a year's worth of transactions at the last minute.

Get set up now, bookmark the login page, and save your Government Gateway credentials somewhere safe. Future you will be grateful.

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