Key takeaways
- The HMRC Self Assessment helpline number is 0300 200 3310, or +44 161 931 9070 from outside the UK.
- The Self Assessment helpline is open Monday to Friday, 8am to 6pm, and is closed on bank holidays.
- HMRC's average call wait across all helplines was 16 minutes 45 seconds in December 2025 and 12 minutes 14 seconds in January 2026.
- The deadline to file online and pay for the 2025 to 2026 tax year is 11:59pm on 31 January 2027, which falls on a Sunday.
- If you cannot pay your Self Assessment bill, call the payment problems line on 0300 200 3820.
- Login, password and error message problems go to the online services helpdesk on 0300 200 3600, not the Self Assessment helpline.
- A Self Assessment return filed late gets an initial £100 penalty, even if no tax is owed.
The HMRC Self Assessment helpline is 0300 200 3310, open Monday to Friday, 8am to 6pm, and closed on bank holidays. It covers returns, payments, notices and Making Tax Digital for Income Tax. Queues lengthen in December and January, so call before the 31 January 2027 deadline rush if you can.
Which Self Assessment number should you call?
The general line handles most Self Assessment queries, but payment problems and login problems have their own numbers. These are the numbers on GOV.UK, checked on 6 November 2026.
| Query | Number | Notes |
|---|---|---|
| General Self Assessment | 0300 200 3310 | Returns, notices, MTD |
| Help submitting a payment | 0300 200 3310 | Have your UTR ready |
| Cannot pay on time | 0300 200 3820 | Payment problems line |
| Login and error messages | 0300 200 3600 | Online services helpdesk |
| Outside the UK | +44 161 931 9070 | Same hours |
All lines open Monday to Friday, 8am to 6pm. HMRC also answers general questions on X at @HMRCcustomers, Monday to Friday 8am to 8pm and Saturday 8am to 4pm, but it cannot discuss your case there.
For other taxes, see our list of HMRC telephone numbers.
What the Self Assessment helpline covers
According to the Self Assessment general enquiries page, last updated on 28 July 2026, the phone line deals with four areas.
- Your Self Assessment returns
- Payments
- Replacement returns or notices
- Signing up for or using Making Tax Digital for Income Tax
HMRC’s digital assistant handles registering or ending Self Assessment, filing and paying, penalty appeals, refunds and activation codes. It can pass you to webchat with an adviser if one is available.
The helpline does not fix online submission errors or lost passwords; those go to the HMRC online services helpdesk. Problems with MTD software go to your software provider.
How long were the January queues?
HMRC does not publish waits for the Self Assessment line alone. Its January 2026 performance data, published on 12 March 2026, shows waits across all helplines last winter.
| Month | Average wait | Calls over 10 minutes |
|---|---|---|
| November 2025 | 13:27 | 52.8% |
| December 2025 | 16:45 | 55.0% |
| January 2026 | 12:14 | 44.6% |
December 2025 had the longest average wait of the 2025 to 2026 year. HMRC’s later data, published on 8 October 2026, shows the average fell to 8 minutes 20 seconds in August 2026. Our guide to the best time to call HMRC sets out the patterns.
Will HMRC open at the weekend before 31 January 2027?
We do not know yet. The 31 January 2027 deadline falls on a Sunday, and HMRC has not published any weekend opening times.
Last year, when 31 January 2026 fell on a Saturday, HMRC opened the phone helpline from 9am to 4pm and webchat from 8am to 4pm that day. It announced this on 28 January 2026. Do not plan around weekend opening; aim to file well before.
What to have ready before you call
The payments page asks for your Self Assessment UTR; the general page does not list what you need. Have these ready anyway.
- Your 10-digit Unique Taxpayer Reference (see how to find your UTR)
- Your National Insurance number
- The tax year the query is about
- Any HMRC letter, statement or penalty notice
- Up-to-date details in your personal tax account, so you pass security
Note the adviser’s name, the date and any reference number.
Key dates for the 2025 to 2026 tax year
These are the deadlines on GOV.UK.
| Deadline | What is due |
|---|---|
| 5 October 2026 | Register for Self Assessment (passed) |
| 31 October 2026 | Paper return (passed) |
| 30 December 2026 | File online to pay through your tax code |
| 31 January 2027 | File online and pay the balance |
If you want HMRC to collect what you owe through your PAYE tax code, read our guide to paying Self Assessment through your tax code.
What happens if you miss the deadline?
You get an initial £100 penalty for a late return. After 3 months, daily penalties of £10 a day apply, up to £900. Late payment adds 5% of the unpaid tax at 30 days, 6 months and 12 months, plus interest. These figures come from HMRC’s penalties page.
What to do now
- File early. Filing in November or early December avoids the worst queues.
- Estimate your bill. Use our Self Assessment calculator to see what you will owe on 31 January 2027.
- Call early in the day. The lines open at 8am.
- Use the right number. Payment problems go to 0300 200 3820, login issues to 0300 200 3600.
Frequently asked questions
What is the HMRC Self Assessment helpline number?
The number is 0300 200 3310. From outside the UK, call +44 161 931 9070.
What are the Self Assessment helpline opening hours?
It is open Monday to Friday, 8am to 6pm, and is closed on bank holidays.
Is the Self Assessment helpline open at weekends in January?
HMRC has not announced weekend hours for January 2027. In 2026 it opened the phone line from 9am to 4pm on Saturday 31 January.
What number do I call if I cannot pay my Self Assessment bill?
Call the Self Assessment payment problems line on 0300 200 3820. It is open Monday to Friday, 8am to 6pm.
Can I pay my Self Assessment bill over the phone?
No. HMRC says you cannot pay your bill on its Self Assessment payments line; you pay online, through the HMRC app, by CHAPS or by cheque.
Sources
Rates, thresholds and rules in this guide were checked against HMRC and GOV.UK guidance on 6 November 2026. Tax rules change, so check the current position on GOV.UK or with a qualified adviser before acting. This guide is general information, not personal advice.