How to Submit MTD Quarterly Updates: Step by Step Guide

Submitting MTD quarterly updates does not need to be complicated. If you have been keeping your digital records up to date throughout the quarter, the actual submission process takes just a few minutes. This guide walks you through every step, from preparation to confirmation.

Understanding What a Quarterly Update Contains

A quarterly update is a summary of your business income and expenses for a three-month period. It is not a tax return — it is simply a snapshot of your financial activity for the quarter.

Each update includes:

• Total income received during the quarter
• Expenses broken down by category (travel, office costs, stock, professional fees, etc.)
• Net profit or loss for the quarter

You do not need to submit individual invoices, receipts, or bank statements. HMRC receives the summarised totals, which feed into your running tax calculation for the year.

The Quarterly Update Calendar

The tax year runs from 6 April to 5 April, divided into four standard quarters:

| Quarter | Covers | Submission deadline | |---------|--------|-------------------| | Q1 | 6 April – 5 July | 7 August | | Q2 | 6 July – 5 October | 7 November | | Q3 | 6 October – 5 January | 7 February | | Q4 | 6 January – 5 April | 7 May |

You have approximately one month after each quarter ends to submit your update. There is no requirement to submit on the deadline — you can submit earlier if your records are ready.

Step 1: Ensure Your Records Are Up to Date

Before submitting, check that all transactions for the quarter have been recorded in your MTD software. This means:

• Bank transactions imported: If you use bank feeds, check that the latest transactions have been pulled through. Most software syncs daily, but it is worth confirming.
• Cash transactions recorded: If you receive cash payments or pay for items in cash, these need to be entered manually.
• Receipts matched: Any receipts you have captured should be matched to the corresponding transactions.
• Categories confirmed: Review the expense categories assigned to each transaction. If your software uses AI categorisation (as Accounted does), most will be correct, but it is good practice to scan through and confirm.

Step 2: Review Your Quarter Summary

Your software should provide a summary screen showing your income and expenses for the quarter. Review this carefully:

• Does the income figure look right? Compare it to your bank statements or invoicing records.
• Are the expense categories reasonable? Look for anything miscategorised — a personal purchase incorrectly tagged as a business expense, or a business cost sitting in the wrong category.
• Are there any missing transactions? If you know you made a purchase that is not showing, add it before submitting.
• Is the profit figure in line with your expectations? If it is significantly higher or lower than you expected, investigate before submitting.

With Accounted, Penny highlights any transactions that look unusual or that she is uncertain about, so you can review them before submission.

Step 3: Make Any Adjustments

If you spot errors during your review, correct them before submitting:

• Recategorise transactions: Move any items to the correct expense category
• Add missing transactions: Enter any cash payments or income that was not captured automatically
• Remove personal items: If any personal spending was accidentally imported via your bank feed, exclude it from your business records
• Adjust for mixed use: If you have expenses that are partly personal and partly business (such as a phone bill), apply the appropriate business use percentage

Step 4: Submit to HMRC

Once you are satisfied that your quarter summary is accurate, submit it through your software. The process varies by provider, but generally involves:

1. Navigate to the MTD submission section of your software
2. Review the summary one final time
3. Confirm that the figures are correct to the best of your knowledge
4. Click submit

Your software sends the data to HMRC via their API. You should receive a confirmation with a submission receipt or reference number. Keep this for your records.

In Accounted, the process is even simpler. Penny prepares your quarterly update automatically and notifies you when it is ready. You review the summary, confirm it, and Accounted handles the rest. If you prefer, you can set it to submit automatically after your review window.

Step 5: Save Your Confirmation

After submitting, save the confirmation from HMRC. This typically includes:

• A submission reference number
• The date and time of submission
• A summary of the figures submitted

Most software stores this automatically, but it is good practice to know where to find it in case HMRC queries your submission later.

What Happens After You Submit

Once HMRC receives your quarterly update, they use it to calculate a running estimate of your tax liability for the year. You can see this estimate through your software or your HMRC online account.

This running estimate is not a bill — it is informational. Your actual tax liability is calculated after you file your final declaration at the end of the tax year.

However, the running estimate is incredibly useful for budgeting. If you can see that your estimated tax bill is £8,000 by the end of Q2, you know to set aside roughly £4,000 more over the remaining two quarters. No more nasty surprises in January.

What If You Make a Mistake?

If you realise after submitting that you made an error, do not panic. You can correct it by:

• Amending the current quarter: Some software allows you to amend a submitted update within a certain window
• Adjusting in the next quarter: Small errors can often be corrected by adjusting the figures in your next quarterly update
• Correcting in the final declaration: The final declaration at year-end is your chance to ensure the full-year figures are accurate

HMRC understands that quarterly figures are provisional and that adjustments may be needed. The final declaration is what matters most for your tax calculation.

Tips for Stress-Free Quarterly Submissions

Stay on top of your records weekly. Spending 15 minutes each week reviewing and categorising transactions means your quarterly update is virtually ready before the deadline arrives.

Set calendar reminders. Even if your software notifies you, set your own reminders for a week before each deadline so you have time to review and resolve any issues.

Use bank feeds. Manually entering every transaction is tedious and error-prone. Automatic bank feeds capture everything and reduce your workload dramatically.

Let AI do the heavy lifting. Software like Accounted uses AI to categorise your expenses automatically. You just need to confirm the suggestions rather than categorise everything from scratch.

Do not aim for perfection. Quarterly updates are summaries, not audited accounts. Get them broadly right and correct any minor issues in the final declaration.

Submit early. There is no advantage to waiting until the deadline. Submit as soon as your records are complete, and you have one less thing to think about.

Frequently Asked Questions

Do I need to submit receipts with my quarterly update? No. You submit summary figures only. However, you must keep your receipts as supporting evidence in case HMRC asks to see them.

Can my accountant submit for me? Yes. If your accountant has agent access, they can review and submit your quarterly updates on your behalf.

What if I miss the deadline? You receive a penalty point. After accumulating 4 points (for quarterly obligations), each subsequent late submission triggers a £200 fine. See our guide on MTD penalties for more detail.

Do I still need to file a Self Assessment tax return? The final declaration replaces your Self Assessment return for the income covered by MTD. If you have other income not covered by MTD, you may still need to report it separately.

MTD is coming. Accounted is already compliant. Start free and be ready before the deadline.