Electricians and Making Tax Digital: wholesale cable, test meters, and site expense logging

An electrical installation can involve several merchant orders before the customer pays the final invoice. Cable, consumer units, accessories and test equipment all leave the bank, but they do not all represent the same type of cost.

Making Tax Digital is easier when your records distinguish materials supplied on jobs, equipment retained by the business and tax deducted by contractors. A merchant statement and a bank feed are useful starting points; the underlying invoices explain what happened.

When Making Tax Digital applies

Making Tax Digital for Income Tax changes how qualifying sole traders and landlords keep records and report income. Under HMRC’s timetable, the starting points are:

• From 6 April 2026, if qualifying income exceeded £50,000 in 2024–25.
• From 6 April 2027, if qualifying income exceeded £30,000 in 2025–26.
• From 6 April 2028, if qualifying income exceeded £20,000 in 2026–27.

Qualifying income generally means gross self-employment and property income combined, before expenses. Salary, pension income and dividends do not count towards this particular test. Check HMRC’s qualifying income guidance, including the treatment of VAT and shorter accounting periods where relevant.

The test uses the relevant earlier tax year; passing a figure during a busy month does not mean you join that day. Exemptions can apply. These rules concern your individual business and property income, rather than a limited company’s Corporation Tax reporting.

Wholesale materials and customer recharges

Cable, consumer units, breakers, sockets, lighting components and EV charging equipment bought to supply on a customer job are normally business materials. Record the purchase and the full customer charge separately, even if a particular component is supplied at cost.

Keep invoices from CEF, Edmundson, Screwfix or your other suppliers, together with returns and credits. A trade account payment can settle several invoices; do not claim the invoices and the settlement as duplicate expenses.

Under the cash basis, eligible costs generally follow payment timing. Traditional accounting can require stock and work-in-progress adjustments. Materials waiting in the van do not have identical timing under every accounting method.

Section 34 of the Income Tax (Trading and Other Income) Act 2005 supplies the business purpose test. Exclude purchases for your own home and retain a clear split where they share a receipt with customer materials.

Test meters, calibration and scheme costs

Multifunction testers, suitable specialist tools and business equipment can qualify for tax relief. Most eligible equipment is deducted when paid for under the cash basis; traditional accounting normally uses capital allowances. Accounting depreciation is not an additional tax deduction.

Calibration, servicing, replacement leads and routine repairs should remain identifiable as maintenance costs. Keep certificates where relevant, as well as the financial invoice. Their technical purpose and the tax record support different needs.

Relevant NICEIC or NAPIT scheme costs and insurance may be allowable where incurred for the existing business. Check what a renewal package covers and avoid claiming included services again. Use the current scheme and membership details applicable to your work rather than copying an outdated trade-body description.

Courses updating your knowledge of the wiring regulations or developing the existing business can qualify under HMRC’s training guidance. Training to start an unrelated trade needs separate assessment. Keep enough detail to show the link with the business you already operate.

Worked example: a CIS payment

Theo is a registered CIS subcontractor paid at the 20% deduction rate. He invoices £3,000 labour and £1,000 materials, which he bought directly for £1,000. Ignore VAT for this illustration and assume the contractor accepts the evidenced direct materials cost.

Theo records £4,000 gross income, the £1,000 materials cost and £600 CIS tax deducted separately. The £600 is not a business expense and does not reduce turnover. It is considered as tax already paid in the annual calculation. HMRC’s subcontractor guidance explains the reporting and credit process.

The contractor must use the rate established through CIS verification; other circumstances can mean 30% or payment without deduction. Keep the payment and deduction statement rather than trying to infer everything from the bank receipt.

Van and site travel

For an eligible vehicle, use a consistent mileage or actual-cost method, subject to previous claims. Mileage replaces the covered purchase and running costs, so fuel and repairs cannot be added again. Keep the business journey evidence needed for your method.

Assess travel to sites on the actual working pattern. The employee temporary-workplace rules are not a shortcut for every sole trader’s journey. Overnight business accommodation and subsistence also require the appropriate business circumstances and records.

Keep CIS and VAT in view

Working for private householders is different from receiving payments from CIS contractors. If you pay subcontractors yourself, contractor verification and monthly reporting obligations may arise alongside your own MTD updates. The CIS overview explains these roles.

VAT also has separate tests. Where registered, check whether the construction domestic reverse charge applies to the actual supply and customer. Do not apply it automatically to every electrical invoice.

Avona AI can support categorisation, while the job invoice, merchant detail and CIS statement establish the required treatment. Review those documents together when a contractor payment arrives.

A manageable quarterly routine

For a business using standard tax-year periods, the 2026–27 quarterly update deadlines are 7 August 2026, 7 November 2026, 7 February 2027 and 7 May 2027. Updates are cumulative: each covers the tax year so far. Calendar update periods are also available, with the same deadlines.

Keep digital income and expense records, reconcile them regularly and send the required totals through compatible software. The Income Tax (Digital Obligations) Regulations 2026 underpin the requirements; HMRC’s digital record-keeping notice explains the applicable directions. A bank feed needs supporting detail wherever a payment conceals fees, private purchases or several transactions.

Normally, record the transaction date, amount and relevant category, retaining supporting invoices or receipts. HMRC’s digital records guidance explains permitted simplifications and digital links where more than one software product is used.

Quarterly updates do not replace the annual tax return. The 2026–27 return is due by 31 January 2028, and normal tax payment dates continue. HMRC is not applying late quarterly update penalties for 2026–27, but digital records and updates are still required. That first-year approach does not waive other filing or payment obligations.

Keep each job’s finances connected

Complete sales, clear material costs and separate CIS credits make reporting more manageable. Avona.app costs £15/month. Avona Concierge, managed by chartered accountants, starts from £60/month for ongoing help with your trade accounts.