HMRC Self Assessment Contact: Phone, Online and Chat Options 2026

Getting through to HMRC can be frustrating, but knowing which channel to use and when can save you hours. This guide covers every contact option for Self Assessment in 2026, along with tips for resolving common issues without calling at all.

The Self Assessment Helpline

The main HMRC Self Assessment helpline is 0300 200 3310. It is open Monday to Friday, 8am to 6pm. Calls from UK landlines and mobiles are charged at the standard geographic rate (the same as any 01 or 02 number).

If you are calling from outside the UK, the number is +44 161 931 9070.

Best times to call: HMRC publishes wait time data and the evidence is consistent -- the lines are busiest in January (ahead of the 31 January filing deadline), in April and May (end of the tax year queries), and on Monday mornings. If you can call mid-week between 10am and noon, or in the afternoon from around 2pm, you are likely to wait less. The absolute worst time is any day in January and the first two weeks of February.

HMRC has also offered a call-back service in some years -- listen carefully to the recorded options as this can let you keep your place in the queue without staying on hold.

The Personal Tax Account (Online)

Your Personal Tax Account (PTA) at www.gov.uk/personal-tax-account is the fastest way to handle many routine queries. You can:

• View your Self Assessment tax return history and tax calculations
• Make or schedule a payment
• Check what you owe and see your payment history
• Update your address, bank details for refunds, and contact preferences
• View your PAYE tax code
• Claim Marriage Allowance
• Check your National Insurance record and State Pension forecast

You log in using Government Gateway. If you do not have an account, registering takes about 10 minutes and requires proof of identity (usually a passport or driving licence and either a recent payslip or P60). Once verified, you can handle most standard Self Assessment tasks without calling.

For Self Assessment-specific tasks, the online SA return filing service at GOV.UK is separate from the PTA but uses the same Government Gateway login.

Webchat

HMRC offers a webchat service for some queries, accessible via the 'Contact HMRC' pages on GOV.UK. Webchat availability has varied over recent years -- it has been withdrawn and reinstated. As of 2026 it is available for certain Self Assessment questions during weekday business hours.

Webchat is particularly useful for quick factual questions: "What is my Unique Taxpayer Reference?", "Has my payment been received?", or "What is the late filing penalty threshold?" A webchat transcript can also be saved, which is useful if you need a record of advice given.

Do not use webchat for complex or disputed matters -- these require a formal written record or a phone call where you can request a reference number.

Agent Helpline

If you use an accountant or tax adviser, they have access to a separate dedicated Agent Helpline: 0300 200 3311. Wait times on the agent line are typically shorter than the main public helpline, which is another reason to consider using a tax professional if your affairs are complex.

Writing to HMRC

For formal disputes, appeals, or anything you want in writing, the postal address for Self Assessment is:

HM Revenue and Customs
Self Assessment
BX9 1AS
United Kingdom

No street address or town is needed -- this PO Box format is official. Always include your Unique Taxpayer Reference (UTR) in any correspondence and keep a copy of what you send. HMRC's published target is to respond to post within 15 working days, though in practice replies can take longer during busy periods.

Resolving Common Issues Without Calling

Many of the most frequent reasons people call HMRC can be resolved online:

"I have not received my SA302 / tax year overview": These are available directly in your PTA under 'Get proof of income'. Mortgage lenders increasingly accept a download from the PTA rather than an HMRC letter.

"I do not know my UTR": Your UTR is on any previous SA notice, letter from HMRC, or tax return. You can also retrieve it through your Government Gateway account under Self Assessment.

"I need to change my payment on account": Use the SA303 process (see our separate guide) -- you can reduce payments on account online via your PTA rather than calling.

"I made an error on my return": You can amend a submitted Self Assessment return online within 12 months of the 31 January filing deadline for that tax year. Go to your return in the PTA and select 'Amend'.

"I think my tax code is wrong": This is managed through PAYE -- your tax code can be viewed and queried via the 'Income Tax' section of the PTA. An incorrect code can be challenged there without a phone call.

Appeals Against Penalties

If you receive a late filing or late payment penalty you want to dispute, you have 30 days to appeal. You can appeal online through the PTA or by completing form SA370. Appeals on grounds of reasonable excuse (serious illness, bereavement, HMRC system failure) are assessed on their merits. Always submit an appeal in writing and keep a copy.

For penalty appeals that are rejected, you can request a statutory review by HMRC, and if still dissatisfied, escalate to the First-tier Tax Tribunal at no cost.