For window fitters & glaziers

MTD for Income Tax for window fitters & glaziers.

Large material orders, customer deposits, FENSA registration and emergency glazing work. Here's how Making Tax Digital for Income Tax applies to window fitters and glaziers, and exactly when it starts.

When does it start for me?

In scope now over £50k, from April 2027 over £30k.

MTD for Income Tax phases in by gross income before expenses. Big window orders pass through your accounts, so your gross turnover can be well above your profit.

Live now
£50,000
In scope from April 2026
Your likely date
£30,000
In scope from April 2027
£20,000
In scope from April 2028
Gross, not profit

A full-house order is a lot of turnover.

Even when most of a job is the windows you bought in, it all counts as gross income for the threshold. Recording the matching purchases as expenses keeps your tax based on the fitting margin.

What records you need →
What's changing

Digital records, four quarterly updates, one final declaration.

When you're in scope, your annual Self Assessment return is replaced by four short quarterly updates and a year-end final declaration, all through recognised software.

Expenses to keep digital

  • Windows, glass and units
  • Sealants, fixings and trims
  • Tools and access equipment
  • Van, fuel and running costs
  • FENSA or similar scheme fees
  • Public liability insurance

Record deposits and supplier orders as they happen so a big order is matched to its income cleanly.

  • Large orders Recorded against the job
  • Deposits Income in the quarter received
  • Emergency work Customer or insurer paid
The glazing detail

The bits specific to your trade.

Deposits and orders

A deposit funds the window order. Recorded in the right quarter, it keeps your figures and cash flow clear.

FENSA as an expense

Certification scheme fees are deductible. Keep them recorded so your expense total stays complete.

Emergency glazing

Call-outs paid by a customer or insurer are income. Record the invoice and the materials against the same job.

Materials pass-through

Units you buy and recharge count as income. Record purchases so you're taxed on the fitting margin.

Why Clear Books

Big orders, clear margins.

When thousands of pounds of units pass through your books, the margin needs to be clear. Clear Books keeps income and purchases matched and gives HMRC exactly what MTD needs.

  • Record deposits and supplier orders against the job
  • Keep FENSA and insurance costs logged
  • Record emergency call-outs cleanly
  • See your gross income against the thresholds
  • Send HMRC-compliant quarterly updates in minutes
  • Free plan available, no timer
The Clear Books MTD for Income Tax submissions screen showing four quarterly updates submitted to HMRC
Q1 update submitted
HMRC recognised
Common questions

Window fitter & glazier MTD FAQ.

When does MTD for Income Tax start for window fitters?
If your gross income is over £50,000 it applies now, from 6 April 2026. Between £30,000 and £50,000, your start date is April 2027, and from April 2028 the threshold drops to £20,000.
How do deposits for window orders work?
A deposit is income in the quarter you receive it, and the units you buy are an expense in the quarter you buy them. Recording both keeps your profit accurate across the job.
Is my FENSA registration a business expense?
Yes. Certification scheme costs such as FENSA are business expenses you record digitally, alongside your insurance, tools and van costs.
How do I record emergency glazing call-outs?
Emergency call-outs, paid by the customer or an insurer, are income you record when you invoice or are paid. Materials go against the same job as an expense.
What else can I claim?
Typical costs include windows, glass and units, sealants and fixings, tools and access equipment, your van and fuel, FENSA or similar scheme fees, and insurance.
Free for sole trader fitters

Know where you stand before the deadline.

Record orders, deposits and call-outs as you go, watch your gross against the thresholds, and be ready to submit when your wave lands.