MTD for Joiners and Carpenters: What HMRC Ignores

April 2026 is closer than your next kitchen fit-out, and if you are a self-employed joiner or carpenter turning over more than £50,000, HMRC has already decided you are first in line for Making Tax Digital for Income Tax.

Not accountants. Not software vendors. You: the person who spent this morning cutting dovetail joints and will spend this evening chasing a builder who owes you £800.

The Threshold That Catches Most Established Joiners

HMRC's rollout of Making Tax Digital for Income Tax Self Assessment (MTD for ITSA) works in waves. From April 2026, sole traders and landlords with qualifying income above £50,000 must comply. The £30,000 threshold follows in April 2027, and a £20,000 threshold has been announced for April 2028, though legislation has not yet confirmed that final date.

For a joiner or carpenter running a one-person operation, £50,000 in turnover is not a fortune. Fit a couple of kitchens a month, take on a staircase refurbishment, add some bespoke furniture commissions and you are there. The threshold refers to gross income, not profit, so your timber costs, tool spend, and van fuel do not reduce the number that triggers compliance.

If your turnover sits between £30,000 and £50,000 you have until April 2027 before MTD becomes compulsory, but voluntary early adoption is possible and may actually reduce your admin burden if you plan ahead rather than scrambling at the deadline.

What MTD Actually Requires, Beyond the Vague Official Line

HMRC's own guidance describes MTD as requiring "digital record-keeping" and "quarterly updates." That sentence does roughly as much work as telling someone to "do some carpentry." Here is what it means in practice for joiners and carpenters.

Digital Records

Every item of income and every allowable expense must be recorded digitally, in software that is compatible with HMRC's MTD API. A spreadsheet counts only if you use bridging software to connect it to HMRC. A shoebox of receipts does not count at all, regardless of how meticulously you have organised it by month.

For a joiner, your digital records need to capture:

• Invoices raised for each job: kitchen fitting, staircase work, bespoke furniture, site carpentry
• Materials purchased: timber, sheet goods, fixings, adhesives, finishing products
• Tool costs: purchases, repairs, and replacement of hand tools, power tools, and machinery
• Van and vehicle costs: fuel, servicing, insurance, and MOT (using either actual costs or HMRC's approved mileage rate of 45p per mile for the first 10,000 miles)
• Workshop costs: rent, utilities, and equipment maintenance if you operate from a dedicated space
• Protective equipment and workwear: steel-capped boots, gloves, safety glasses
• Professional costs: public liability insurance, any trade association memberships, accountancy fees

Quarterly Updates

Four times a year you must submit a summary of your income and expenses to HMRC via your MTD-compatible software. The quarters align with the tax year:

• Quarter 1: 6 April to 5 July, submitted by 5 August
• Quarter 2: 6 July to 5 October, submitted by 5 November
• Quarter 3: 6 October to 5 January, submitted by 5 February
• Quarter 4: 6 January to 5 April, submitted by 5 May

Alternatively, HMRC permits a calendar-month alignment if you choose to adopt it from the start. Either way, these are summaries, not final tax calculations. You are not paying tax quarterly. You are sending HMRC a snapshot of your trading so they can see your business is active and your records are being maintained.

End of Period Statement and Final Declaration

After the fourth quarter, you still submit an End of Period Statement confirming your figures are correct, followed by a Final Declaration that replaces the old Self Assessment return. This is where your tax bill is calculated. Think of the quarterly submissions as rough sketches and the Final Declaration as the finished piece.

For a thorough walkthrough of that final stage, see How to Submit an End of Period Statement for MTD.

The Expenses Joiners and Carpenters Routinely Miss

This is where the financial stakes become real. HMRC's digital record requirement is not simply a compliance exercise: it forces you to capture every cost systematically, which means you stop leaving money on the table. The Handyman Sole Trader Tax UK: What You're Leaving on the Table post covers the broader category, but joiners have specific expense patterns worth naming.

Timber offcuts and waste: If you purchase a full sheet of MDF for a built-in wardrobe and use 70% of it, the full cost of the sheet is still an allowable expense. You do not reduce it by the offcut percentage.

Tool depreciation versus the Annual Investment Allowance: If you buy a £1,200 table saw, you can claim the full cost in the year of purchase under the Annual Investment Allowance rather than depreciating it over several years. Many joiners do not know this and underclaim significantly.

Workshop from home: If you run a workshop in your garage or outbuilding, you can claim a proportion of your home's running costs. HMRC requires you to calculate this based on floor area and hours of use. It is legitimate, documented, and widely underclaimed.

Training and CPD: Courses in new joinery techniques, finishing methods, or business skills directly related to your trade are allowable. A course on running a joinery business is deductible. A general degree is not.

Site parking and congestion charges: If you are fitting kitchens in central London or another city with a daily parking or clean air zone charge, those costs are allowable when travelling to client sites.

The point of MTD's digital record requirement is that these expenses only save you tax if you record them. A sole trader earning £65,000 gross with £18,000 in allowable expenses pays income tax and Class 4 National Insurance on £47,000. Fail to record £3,000 of legitimate tool and material costs and you are handing HMRC roughly £1,050 you did not owe, based on combined income tax at 20% and Class 4 NI at 9% in the basic-rate band.

The Penalty System Nobody Explained to You

HMRC replaced the old fixed late-filing penalties for Self Assessment with a points-based system for MTD. Miss a quarterly deadline and you accumulate a penalty point. Reach four points and you receive a £200 fine. After that, every subsequent late submission during the same period adds another £200.

Points expire after two years of clean submissions, but that means two years of maintaining a perfect record while potentially also dealing with a cash-flow pinch from the fine itself.

For joiners with seasonal income patterns, where a quiet January might also be when your vehicle needs repair and your tax software feels like the least urgent problem, the timing is awkward by design. HMRC does not offer a "trades with variable workload" exemption. If you want to understand exactly what late submission costs across different scenarios, What Happens If You Miss an MTD Deadline: The Real Cost does the maths.

Choosing Software That Fits a Joiner's Working Day

The software market for MTD compliance ranges from full accounting suites aimed at businesses with staff and complex VAT requirements to lightweight mobile apps built for sole traders who want to photograph a receipt and move on.

For a self-employed joiner or carpenter, the relevant questions are:

Can I log expenses from my phone on site? Most jobs involve purchasing materials at a merchant that morning, fitting them by afternoon, and invoicing by evening. Software that requires desktop entry defeats the point.

Does it handle CIS deductions? If you work on construction sites where the main contractor deducts Construction Industry Scheme tax at source (typically 20%), your software needs to record those deductions correctly so they offset your year-end liability. CIS is one of the most misunderstood aspects of sole trader tax in the construction trades; the Construction Worker Sole Trader Tax: What HMRC Tracks post covers it in detail.

What does it actually cost? HMRC chose not to build a free submission tool for sole traders, which means the compliance cost falls entirely on you. Some well-known accounting platforms charge upwards of £30 per month, or £360 per year, for features a sole trader will never use. That is a tax on tax compliance. Simpler apps aimed specifically at sole traders cost significantly less and cover everything MTD requires without the overhead.

If you have been using a spreadsheet and are reluctant to abandon a system that works for you, bridging software can read your spreadsheet data and submit it to HMRC's API without you changing how you record things day-to-day. It is not the cleanest long-term solution but it is a legitimate and sometimes sensible transitional approach. For help making that transition without losing your data, How to Switch to MTD Software Without Losing a Day's Work is worth reading before you make any decisions.

The CIS Complication Most Joiners Underestimate

A significant proportion of joiners and carpenters work on a mix of direct-to-consumer projects and subcontracted work through builders, developers, or main contractors. The moment you step onto a CIS-registered site as a subcontractor, the contractor deducts 20% from your labour payments (or 30% if you are not registered with CIS) and pays it directly to HMRC.

This creates a specific record-keeping challenge under MTD. Your quarterly submissions must show your gross income, not the net amount you received after CIS deductions. If you invoiced £8,000 for a fit-out but received £6,400 because the contractor retained 20%, your MTD records must show £8,000 as income. The £1,600 CIS deduction is then recorded separately and offsets your final tax bill.

Getting this wrong understates your income in your quarterly submissions and creates a discrepancy that HMRC will eventually investigate. Your MTD software must handle CIS records explicitly, not just log bank deposits.

A Realistic Picture: Jamie the Joiner

Jamie is a self-employed joiner in the East Midlands, turning over £58,000 a year. He fits kitchens for a local builder under CIS about 40% of the time and takes direct consumer jobs for the rest. His annual expenses run to roughly £21,000: timber and sheet materials, fixings, his Transit van, tools, insurance, and a shared workshop space.

Under the old Self Assessment system, Jamie collected receipts in a folder, handed them to his accountant in January, and paid a £450 fee for the return. He regularly forgot to claim tool repairs and did not realise his workshop proportion was allowable, leaving perhaps £2,000 of legitimate expenses unclaimed each year. At a combined marginal rate of 29%, that is £580 HMRC kept that it was not entitled to.

Under MTD, Jamie needs to log income and expenses quarterly. The workload is not dramatically higher if he photographs receipts as he goes and reconciles monthly rather than yearly. But the discipline of quarterly submissions means his accountant (or his MTD app) flags the missing workshop claim and the tool repairs in real time rather than six months after the fact. Over five years, that is nearly £3,000 returned to Jamie that currently goes to HMRC by default.

The compliance cost is real: a good sole-trader MTD app costs perhaps £10 to £15 per month, or £120 to £180 per year. That is less than Jamie's current accountancy fee for a single return. The net financial position under MTD, if Jamie uses the system properly, is likely better than the status quo.

What to Do Before April 2026

If your turnover exceeds £50,000 and you are not already keeping digital records, the window to act comfortably is now. Scrambling in March 2026 means choosing software under pressure, importing historical records hastily, and submitting your first quarter without understanding what you are doing.

A practical sequence:

1. Check your threshold: Review your last Self Assessment return. If your turnover was above £50,000, you are in scope for April 2026.
2. Register for CIS as a subcontractor if you work on contractor sites and have not already done so, to ensure the 20% deduction rate rather than 30%.
3. Choose MTD software that handles CIS deductions, allows mobile expense logging, and costs proportionately for a sole trader rather than a ten-person firm.
4. Begin digital record-keeping now, even before the mandate, so you have a clean transition rather than a gap in your records.
5. Review your allowable expenses: use the Annual Investment Allowance for tools, claim your workshop costs, and log every site-related journey.

April 2026 is the deadline HMRC set. The irony is that the joiners who start now will spend less time on it than those who wait.