Making Tax Digital for Income Tax: The Five Submission Problem

Five times a year. That is how often HMRC will expect you to submit information under Making Tax Digital for income tax, once the rules come into force for sole traders from April 2026. Not once, as you do now with your Self Assessment return. Five times.

If nobody has told you that yet, you are not alone. And if you have heard it but assumed it would be simple, this post is for you.

What Making Tax Digital for Income Tax Actually Is

The phrase 'Making Tax Digital for income tax' sounds like a tidying-up exercise. A bit of admin modernisation. Perhaps the digital equivalent of switching from a paper ledger to a spreadsheet.

It is not. It is a fundamental restructuring of how you report your income to HMRC, and the workload it creates is proportionally larger than most sole traders expect.

Here is the structure in plain terms. Currently, you file one Self Assessment return per year, covering the previous tax year, with a deadline of 31 January. Under Making Tax Digital for income tax, you will instead:

• Submit a quarterly update covering April to June, due by 5 August
• Submit a quarterly update covering July to September, due by 5 November
• Submit a quarterly update covering October to December, due by 5 February
• Submit a quarterly update covering January to March, due by 5 May
• File a final declaration (the replacement for your Self Assessment) by 31 January the following year

That is five separate submissions per year, every year, for as long as you remain self-employed above the income threshold.

Who Is Affected, and When

HMRC has set a tiered rollout. If your total gross income from self-employment or property exceeds £50,000, you must comply from 6 April 2026. If it exceeds £30,000, your start date is 6 April 2027. A further expansion to those earning above £20,000 is expected from April 2028, though the legislation for that threshold is not yet finalised.

The income figure that matters is your gross turnover, not your profit. So if you are a self-employed electrician turning over £55,000 but spending £20,000 on materials, tools, and a van, your profit might be £35,000 but your MTD obligation kicks in based on the £55,000 turnover figure.

This distinction catches people out. A plumber who invoices £52,000 a year but clears £30,000 after costs is fully in scope from April 2026, not April 2027. If you are uncertain where you stand, HMRC's own guidance on the thresholds is a reasonable starting point, though it is worth checking annually given the history of changes to this legislation.

For a deeper look at whether you might slip under the threshold, MTD Under the Threshold: Are You Actually Safe? covers the edge cases in detail.

The Quarterly Update: What You Are Actually Sending

A quarterly update is not a full tax return. HMRC is at pains to say so, and technically that is correct. But it is also not as simple as pressing a button.

Each update requires you to report your total income and total expenses for that three-month period, categorised into HMRC's defined categories. You are not calculating your tax bill at this point; you are providing HMRC with a running summary of your trading activity. HMRC will then show you an estimated tax position, though this is not a final liability.

The practical challenge is that you need to have kept digital records throughout the quarter to make this submission accurately. If you have been collecting receipts in a shoebox and reconciling everything in January, that workflow is over. Quarterly updates require quarterly record-keeping.

For most tradespeople and freelancers, this means:

• Logging every invoice as it is raised
• Recording every business expense as it is incurred
• Categorising transactions correctly (materials vs. travel vs. professional fees, for example)
• Submitting a summary to HMRC every thirteen weeks, using approved software

The software requirement is not optional. HMRC will not accept a quarterly update through its own basic portal for most sole traders. You need a piece of third-party software that connects to HMRC's API. That software costs money, in almost every case. Free Software for Making Tax Digital: What HMRC Won't Tell You explains the few exceptions in full.

What Happens If You Miss a Deadline

HMRC has designed a new penalty framework specifically for MTD for income tax, and it works on a points system. Miss a submission deadline and you receive one penalty point. Accumulate enough points within a 24-month window and you face a financial penalty.

For quarterly filers, the threshold is four points, which triggers a £200 fine. After that, every subsequent missed deadline adds another £200. The points reset only once you have filed on time for a full year and cleared your outstanding submissions.

In practice, if you miss all four quarterly deadlines in a single year, you are at four points and facing a £200 penalty immediately. Miss the same four deadlines in year two, and you are looking at £200 for each missed submission on top of the initial fine. The maths escalates quickly.

The final declaration carries a separate penalty structure, closer to the existing Self Assessment late-filing regime. Miss the 31 January deadline and you face an immediate £100 fine, with daily penalties accruing after three months.

The Final Declaration Is Not a Formality

One of the more misleading impressions created by HMRC's communications is that the final declaration is simply a confirmation step. You have already sent four quarterly updates, so surely you just sign off on the numbers?

In reality, the final declaration is where the substantive tax work still happens. This is where you:

• Claim allowable reliefs (pension contributions, trading losses brought forward, Marriage Allowance)
• Report any income that sits outside your quarterly updates (dividends, savings interest, rental income if it was not in your quarterly submissions)
• Confirm your Class 4 National Insurance position
• Adjust for any errors or corrections in the quarterly figures

For a sole trader earning £65,000 with a pension contribution and some savings interest, the final declaration is not a rubber stamp. It is a proper accounting exercise. The quarterly updates get HMRC partway there; the final declaration closes the loop.

If you currently use an accountant for your Self Assessment, this is worth discussing with them now. Do I Need MTD If I Have an Accountant? addresses exactly how that relationship changes under the new regime.

The Real Cost: Time, Not Just Money

Much of the coverage of Making Tax Digital for income tax focuses on the software cost. That is legitimate; ongoing subscription fees for MTD-compatible software typically run from £10 to £40 per month, depending on the provider and feature set. Making Tax Digital Software: Stop Paying for Features You'll Never Use makes the case for choosing carefully.

But the time cost is harder to quantify and arguably more significant for a tradesperson whose billable hours are finite.

Consider a self-employed electrician, turning over £60,000 a year, who currently spends two days in January pulling together receipts and bank statements for their accountant. Under MTD for income tax, the same work has to happen four times a year, in much smaller chunks. The total hours might be comparable, or even lower with good digital habits, but the distribution changes dramatically.

Four deadlines a year means four interruptions to your working rhythm. If your busiest period is October to December, the 5 February deadline falls directly in the aftermath of your most demanding quarter. You cannot defer it. You cannot batch it with the rest. It is due when it is due.

HMRC's own impact assessment acknowledged that the transition would impose a one-off familiarisation cost on businesses. What it was less forthcoming about was the ongoing cognitive load of managing compliance across five annual deadlines rather than one. Making Tax Digital: HMRC's Biggest Gamble With Your Time covers this argument in more depth.

Choosing the Right Software Before April 2026

The software decision is the most consequential practical step you can take right now. HMRC maintains a list of compatible software products, but the list is long, the pricing varies enormously, and the feature sets are poorly matched to the needs of a sole trader who simply wants to log income, log expenses, and submit quarterly.

The key questions to ask before signing up to anything:

• Does it connect directly to HMRC's MTD API for income tax (not just VAT)?
• Can I submit quarterly updates from the software without needing an accountant to do it?
• Is the pricing transparent, with no hidden per-submission fees?
• Does it work on a phone, so I can log expenses on site rather than at a desk?

For a more structured comparison, MTD Software for Sole Traders: Cut Through the Noise runs through the main options with the sole trader in mind.

TapTax is built specifically for this use case: quarterly updates, simple expense categorisation, and a direct HMRC connection, without the complexity of full accounting software designed for multi-employee businesses.

The Honest Summary

Making Tax Digital for income tax is not a scam, and it is not going away. The underlying logic, that real-time data produces better tax estimates and reduces errors, is reasonable enough. The execution, however, places a significantly higher administrative burden on sole traders and delivers the immediate benefit to HMRC rather than to you.

Five submissions a year. That is where we started, and that is the number to hold in your mind as you plan for April 2026. Four quarterly updates and one final declaration, each with its own deadline, its own penalty exposure, and its own requirement for current, accurate, digitally-held records.

The sole traders who will find this manageable are those who build a light, consistent record-keeping habit now, choose software that fits their actual workflow rather than an accountant's, and do not leave familiarisation until March 2026.

If you want to understand exactly what that habit looks like in practice, TapTax is worth ten minutes of your time today at taptax.co.uk.