How do I submit a quarterly update to HMRC, step by step?

Quick answer: You submit a Making Tax Digital (MTD) quarterly update through your HMRC-compatible software in four steps: keep digital records of income and expenses, review your categorised totals, send the cumulative quarterly update to HMRC, then repeat each quarter and finish with a final declaration. The updates are due 7 August, 7 November, 7 February and 7 May. See your exact dates with the deadline calculator — or read the full walkthrough below.

Under MTD for Income Tax, the once-a-year Self Assessment return becomes five submissions: four quarterly updates and a final declaration. The quarterly update is the one you will do most often, so it pays to understand it well. The good news is that, with the right software, each one is quick — most of the work is simply keeping your records tidy as you go.

Here is the process from start to finish.

Before you start: what a quarterly update is

A quarterly update is a summary of your business income and expenses, sent to HMRC through compatible software. Two things are worth knowing up front:

• The figures are cumulative totals by category — each update covers the year so far, not just the latest three months in isolation.
• A quarterly update is not your final tax position. You finalise everything later, at the final declaration, where you claim allowances and reliefs and confirm other income.

That cumulative design is forgiving: if a figure shifts, the next update reflects the corrected running total. Now let's walk through it.

Step 1: Keep digital records of income and expenses

Everything starts with your records. From the beginning of the tax year you must keep digital records of your business income and expenses, capturing the date, amount and category of each transaction.

You can record these directly in MTD software, or use bridging software that links a spreadsheet to HMRC. The key is that the records are digital and the link to HMRC is maintained — you cannot simply retype a paper total at quarter-end.

The more consistently you record transactions through the quarter, the less there is to do when the deadline arrives. For a full breakdown of what counts, see what records you need for MTD.

Step 2: Review your categorised totals

As the quarter draws to a close, open your software and review the totals it has built up by category. This is your chance to:

• Check that income has been recorded in full.
• Make sure expenses are sitting in the right categories.
• Spot anything uncategorised or duplicated.

Because the update reports totals by category, a few minutes tidying here keeps your numbers clean and consistent across the year. You are not trying to reach a final answer — just making sure the running totals are accurate.

Step 3: Submit the cumulative quarterly update via software

When your totals look right, you send the update through the software to HMRC. There is no separate HMRC website to log into for this — compatible software connects directly to HMRC's systems.

The update contains your cumulative totals by category for the year to date. The four quarterly deadlines are fixed:

• 7 August (first quarter)
• 7 November (second quarter)
• 7 February (third quarter)
• 7 May (fourth quarter)

Mark these in your calendar, or let the deadline calculator map them out for your circumstances. Bear in mind that 2026/27 is a soft-landing year for quarterly-update points, so HMRC is taking a lighter touch on late quarterly updates in the first year — but it is still wise to build the habit early.

Step 4: Repeat each quarter

Each quarter you repeat the same rhythm: keep records → review totals → submit the cumulative update. Because each update restates the year-to-date position, your later submissions naturally pick up any corrections you have made since the last one. By the fourth update you will have a complete cumulative picture of the year.

If you fall into a quarterly routine — a quick weekly or monthly catch-up on records, then a short review before each deadline — the updates rarely take long.

Step 5: Finish with the final declaration

The four quarterly updates are not the end. After the tax year you complete a final declaration by 31 January, which replaces your Self Assessment return. This is where you:

• Finalise your figures.
• Claim allowances and reliefs.
• Confirm any other income (such as employment, dividends, interest or pensions).

So across a full year you make five submissions: four quarterly updates plus the final declaration. Keeping good digital records throughout makes the final declaration far simpler, because the underlying numbers are already in order.

A note on penalties

MTD uses a points-based late-submission system — reach four points and you face a £200 charge. Late payment charges are separate: 3% at day 15, a further 3% at day 30, then 10% a year charged daily thereafter. The soft-landing on quarterly-update points for 2026/27 softens the first year, but getting into a reliable routine from the start is the best protection.

Frequently asked questions

Do I log into the HMRC website to submit a quarterly update? No. You submit through your HMRC-compatible software, which connects directly to HMRC. HMRC does not provide its own software for this.

Are quarterly updates the same as my tax return? No. Quarterly updates are cumulative summaries of income and expenses. Your final position is set at the final declaration by 31 January, which replaces the Self Assessment return.

What are the quarterly update deadlines? 7 August, 7 November, 7 February and 7 May. Use the deadline calculator to confirm yours.

What if I make a mistake in a quarterly update? Because updates are cumulative, the next update reflects the corrected year-to-date totals, and everything is finalised at the final declaration. Keeping accurate digital records reduces errors in the first place.

Do I still file a Self Assessment return as well? No. Once you are mandated for MTD, the final declaration replaces the Self Assessment return. Not sure if you are mandated? Use the scope checker.

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Guidance only, not tax advice. Based on HMRC rules as at June 2026.

Related guides: How to register for MTD as a sole trader · What records do I need to keep for MTD? · Do I need an accountant for MTD?