Repair Shop Accounting: A Practical UK Bookkeeping Guide

By Sajad, Founder at Cellbot — 25 years in the tech repair industry

Published: 2 September 2025 · Editorially reviewed: 26 August 2026 · Qualified UK accountant review pending

Good repair shop accounting starts with one reliable link: every payment and part should trace back to a job. Record the sale, payment method, parts used and any refund against the same job; reconcile cash and card takings daily; then review stock, debtors, VAT and margins each month.

That process matters more than the brand of accounting software. It gives your bookkeeper evidence they can follow and gives you numbers you can use to price work and control cash.

This UK guide is general information, not tax or accounting advice. The treatment of stock, deposits, warranties and VAT depends on your business structure and circumstances, so confirm material decisions with a qualified accountant or HMRC.

Quick answer: make the repair reference the join between authorisation, parts, invoice, payment, refund and warranty work. Reconcile cash, card and bank evidence on a fixed cadence, investigate differences rather than posting unexplained adjustments, then give a qualified accountant a ledger they can trace back to jobs.

!A repair-shop ledger control loop connecting the work order, invoice and payment, parts and stock, reconciliation, and management or tax review

The repair-to-ledger trail

A completed job can create several different records:

Avoid recording only the card total or bank deposit. A card settlement may combine several jobs and deduct fees. Your records should let you reconcile the gross sales, card fees and net bank receipt without inventing a balancing figure.

Download the repair-shop month-end control register. It is an exception and evidence log, not a chart of accounts or tax return. Use the same control IDs each month so unresolved differences, changed thresholds and reviewer sign-off remain visible.

The repair work-order guide defines the job-level evidence that should exist before a transaction reaches the ledger.

A chart of accounts that fits repair work

Keep the categories useful but small. A typical repair business may separate:

• repair labour income;
• parts supplied with repairs;
• accessories and refurbished-device sales;
• parts and consumables purchased;
• year-end stock or cost of sales, as advised for your accounting basis;
• refunds, warranty rework and write-offs;
• card processing fees;
• subcontracted repair costs;
• rent, utilities, insurance, software and marketing; and
• customer deposits or payments on account.

Do not create a ledger code for every screen model. Keep model-level detail in the repair or stock system and summarise it appropriately in the accounts. The job reference should connect the two.

Cash basis or traditional accounting?

For many sole traders and partnerships, cash basis is now the default method for calculating taxable profits. It generally records income when received and expenses when paid. Traditional accounting records income and expenses when invoiced or billed and includes year-end debtors, creditors and stock adjustments.

Limited companies prepare company accounts and do not use the Self Assessment cash-basis rules. Stock-heavy or growing businesses can also need a clearer management view than their tax basis alone provides.

The important repair-shop point is not to assume that every parts purchase must always be treated in one particular way. The correct tax and accounts treatment depends on your structure, accounting basis and facts. Keep supplier invoices, quantities and stock counts so your accountant can apply the right treatment.

See HMRC's cash basis guidance and self-employed record requirements.

Daily, weekly and monthly bookkeeping

Every trading day

1. Close or update each completed job with its invoice total, parts and payment method.
2. Record refunds, deposits and warranty work separately rather than editing the original sale without a trail.
3. Count the cash drawer and explain any difference.
4. Compare card-terminal totals with the repair-system payment report.
5. Save purchase receipts and supplier invoices while the transaction is still recognisable.

Every week

1. Match bank transactions and card settlements to recorded sales and costs.
2. Check open jobs, uncollected devices and unpaid commercial invoices.
3. Review parts received but not entered, and parts fitted but not allocated to a job.
4. Investigate negative stock, duplicate payments and unexplained refunds.
5. Move tax or VAT cash to a separate reserve if that is part of your cash plan.

Every month

1. Reconcile every bank, cash and card account to the month end.
2. Review sales, gross contribution and overheads against the previous month and budget.
3. Count high-value and fast-moving parts; investigate material differences.
4. Check creditors, customer deposits, overdue invoices and upcoming tax payments.
5. Lock or close the period after corrections so later edits remain visible.

The result should be a short exception list, not a month of transactions to reconstruct at year end.

The repair-shop cash-flow guide owns the forward-looking base and downside forecast. Accounting records what has happened; a cash forecast tests what the business can still afford to do.

Record parts, stock and write-offs

Record each purchase from the supplier invoice, including delivery charges and any VAT shown. In the stock system, retain the part identity, quantity, unit cost, supplier and receipt date. When a technician uses it, allocate it to the job.

Also give damaged, returned and cannibalised parts a real status. A failed screen sent back for supplier credit is not the same as one damaged during fitting. A part removed from a donor device still has a source and an estimated cost decision that should be documented consistently.

At a stock count:

• stop or control stock movements while counting;
• count physical units rather than accepting the software figure;
• separate saleable, defective, return-pending and obsolete stock;
• retain the count sheets and adjustments; and
• have material write-offs approved by someone other than the counter where possible.

GOV.UK lists stock owned at year end and the stocktaking used to calculate it among the records a limited company must keep. See company and accounting records.

Treat cash, deposits and refunds clearly

Cash sales need the same job and receipt trail as card payments. Count the drawer to a fixed float, record paid-outs separately and bank cash regularly. Do not use cash takings for purchases without recording both sides of the transaction.

A booking deposit may not have the same accounting or VAT treatment as a completed repair. Label it as a deposit or payment on account, connect it to the customer and job, and record what happens if the customer cancels or the repair cannot proceed. Ask your accountant how deposits should appear in your accounts and VAT records.

For refunds, retain the original invoice, credit note, payment evidence and reason. That protects the customer and stops an unexplained negative sale from hiding a process or fraud problem.

Connect repeat work to the repair warranty control and defective supplier parts to the RMA control record. A supplier credit, customer remedy and internal rework cost are related events, not one interchangeable negative sale.

Monitor the VAT threshold correctly

VAT registration is based on taxable turnover, not profit. The current compulsory threshold is £90,000. You must normally register if taxable turnover for the last 12 months goes over that figure, or if you expect it to go over £90,000 in the next 30 days.

The first test is rolling, so check it every month rather than only at your financial year end. Maintain a simple schedule showing the taxable turnover for each month and the trailing 12-month total.

HMRC's VAT registration guidance explains the tests, deadlines and effective registration dates. If you approach the threshold, obtain advice before changing prices or issuing future-dated quotes. Do not assume that separating labour and parts on an invoice changes the VAT treatment of the overall supply.

VAT-registered businesses must keep the required digital records and submit VAT returns using compatible software unless exempt. Check Making Tax Digital for VAT.

Check Making Tax Digital for Income Tax

Making Tax Digital for Income Tax began on 6 April 2026 for qualifying sole traders and landlords with total qualifying income over £50,000 for 2024 to 2025. The scheduled thresholds are over £30,000 for 2025 to 2026, starting 6 April 2027, and over £20,000 for 2026 to 2027, starting 6 April 2028.

Qualifying income is gross income from self-employment and property before expenses and tax; it is not the same as profit. Eligible people use compatible software to keep digital records, send quarterly updates and submit their tax return.

Check the current HMRC test rather than relying on an old article or software advert: find out if and when you need to use Making Tax Digital for Income Tax.

Work out job contribution before overheads

Use a consistent job-level calculation to test pricing. For example, assume a repair is sold for £120 excluding VAT and has these direct costs:

Part and delivery | £38

Direct technician time | £24

Card fee and job-specific consumables | £4

Contribution before overheads | £54

The £54 is not taxable profit and not money available to withdraw. It still has to cover rent, non-productive wages, insurance, software, marketing, warranty rework, tax and other overheads. The example is illustrative; use your own costs and agree with your accountant how labour and overheads should appear in formal accounts.

Review contribution by repair type, not just total revenue. A popular repair can consume cash if parts are expensive, repeat work is high or prices have not moved with supplier costs.

Choose software by control, not brand

The accounting package and repair system should together support the workflow you need. Before choosing or integrating anything, test whether you can:

• export invoices, credit notes, payment types and tax information;
• preserve a stable job or invoice reference;
• separate gross sales, card fees and net settlements;
• prevent duplicate imports;
• correct an error without erasing the audit trail;
• control who can refund, discount or edit closed jobs; and
• give an accountant access without sharing an owner's login.

Do not buy a package because an integration logo is displayed. Ask which records move, in which direction, how often, and what happens when a sync fails. Run a small test month and reconcile it before relying on automation.

Records to retain

Keep enough evidence to support every figure, including sales invoices, purchase invoices, bank statements, card reports, till or cash records, payroll information, VAT records, stock counts, credit notes and relevant contracts.

Retention periods differ. Self-employed people generally keep records for at least five years after the 31 January submission deadline for the relevant tax year. Limited companies generally keep accounting records for six years from the end of the relevant financial year, with circumstances that require longer retention. Check the current rules for your structure rather than applying one blanket period.

Use the official self-employed record guidance and limited-company record guidance.

Month-end checklist

• All bank, card and cash balances reconcile.
• Every completed job has a final invoice and payment status.
• Refunds and discounts have supporting notes and approval.
• Supplier invoices and credits are entered once.
• High-value stock differences are investigated.
• Deposits and unpaid invoices are reviewed.
• Rolling 12-month taxable turnover is checked.
• VAT and tax deadlines are on the cash forecast.
• Repair categories with weak contribution or repeat work are flagged.
• The period is closed after review.

If one of these checks repeatedly fails, fix the operating step that creates the bad data. Month-end journals should not become a substitute for accurate job records.

What changed in this review

The 26 August 2026 review added a reusable month-end exception register, a repair-to-ledger control graphic, explicit work-order, cash-flow, warranty and RMA boundaries, and a fresh check of HMRC's VAT and Making Tax Digital timetables. Vendor rankings, invented shop averages and tax-treatment shortcuts remain excluded.

Related guides

Use the repair shop pricing guide to turn job costs into defensible prices, the inventory management guide to control parts movement, and the repair shop KPI guide to decide which numbers deserve regular review.

Cellbot can help keep repair jobs, invoices, payments and parts activity connected. Confirm the current workflow and integrations on the features page before choosing an accounting setup.