Should a plumber ask for a deposit before starting work?

Yes — for any job with significant material costs or duration, a deposit is standard and strongly advisable. It protects you if the customer cancels after you have ordered parts, and it demonstrates the customer is serious. A 25–50% deposit is the norm for bathroom fits, boiler installations, and larger plumbing projects. For routine call-out jobs, payment on completion is standard.

What should a plumber's deposit invoice include?

A deposit invoice should include all the standard invoice elements (your business details, customer details, unique invoice number, date) plus: a clear description of the job the deposit relates to, the total agreed quote amount, the deposit percentage and amount, your bank details for payment, and the expected start date. Label it clearly as 'Deposit Invoice' so it cannot be confused with the final invoice.

How do I show a deposit on a plumber's final invoice?

List the deposit as a line item deduction on the final invoice. For example: 'Less deposit paid 15 June 2026 (Invoice DEP-0012): −£500.00'. The final invoice should show the total job value, then the deposit deduction, then the balance due. This gives the customer a clear, transparent record of what they have already paid and what remains.

Is VAT charged on a plumber's deposit invoice?

Yes, if you are VAT-registered. VAT is due on deposits at the time the deposit is paid (the tax point is the earlier of the date you receive the payment or the date you issue the deposit invoice). Apply VAT at the relevant rate to the deposit amount, just as you would to the full invoice.

What happens if a customer cancels after paying a deposit?

If a customer cancels after you have commenced work or ordered materials, you are generally entitled to keep the deposit to cover your costs and losses — provided your terms and conditions state this clearly. If no work has been done and no materials ordered, the right to keep the full deposit is less clear under consumer law. For large deposits, state your cancellation policy explicitly in your quote and in any written agreement.

Plumber Deposit Invoice UK: How to Structure Staged Payments (2026)

When Should a Plumber Ask for a Deposit?

Call-out / small repair (under £300)

No deposit — payment on completion is standard

Medium job — tap replacement, radiator fit, small bathroom upgrade (£300–£1,000)

Optional — 25–50% deposit is reasonable and increasingly common

Larger jobs — full bathroom, boiler installation, heating system (£1,000+)

50% deposit before materials are ordered is standard practice

Multi-day projects — bathroom renovation, underfloor heating, new heating system

Staged payments: 50% upfront, stages at milestones, 10–15% on completion

Always state your deposit requirement in your written quote — before the customer agrees to the work. Springing it on them after they have said yes creates friction. A customer who has read your quote and accepted it knowing a deposit is required will pay it without complaint.

What Goes on a Deposit Invoice

A deposit invoice is a formal document requesting partial payment before work commences. Label it clearly as a deposit invoice — not a standard invoice — to avoid confusion.

Example deposit invoice

DEPOSIT INVOICE

Dave Smith Plumbing

Invoice no: DEP-0012

Date: 9 June 2026

For

Mrs Sarah Collins

22 Birchfield Road

Manchester M14 5AB

Deposit for: Full bathroom installation at above address

Full quote reference: QT-0089 (dated 5 June 2026)

Total agreed quote value£3,200.00

Deposit required (50%)£1,600.00

Payment due before work commences (estimated start: 16 June 2026)

Bank transfer to: Dave Smith · Sort code 12-34-56 · Account 87654321

The deposit invoice number (DEP-0012 in the example) is separate from your main invoice sequence. Use a DEP- prefix to keep them distinct from standard invoices. This keeps your records clean and makes it easy to identify deposit invoices in your history.

How to Structure the Final Balance Invoice

When the job is complete, issue a final invoice that shows the full job value and deducts the deposit already paid. The customer should see exactly what they owe and why.

Example final invoice (with deposit deducted)

Labour — bathroom installation (4 days @ £400/day)£1,600.00

Materials — bath suite, taps, toilet, shower enclosure£980.00

Materials — pipework, fittings, waste connections£220.00

Tiling (subcontracted, passed through at cost)£400.00

Subtotal£3,200.00

Less deposit paid (Invoice DEP-0012, 12 June 2026)−£1,600.00

Balance due£1,600.00

Payment due within 7 days of completion · Bank transfer details as before

Staged Payments for Larger Projects

For multi-week or high-value projects, staged payments tied to milestones are best practice. They protect you (you are not owed a large sum at the end of a long job) and they protect the customer (they pay for work as it is done, not in advance of an unknown quantity).

Stage	When to invoice	Typical %
Stage 1 — Deposit	Before work starts / materials ordered	30–50%
Stage 2 — First fix complete	When first fix plumbing is done (before plastering)	25–30%
Stage 3 — Second fix complete	When fixtures are installed and tested	20–25%
Stage 4 — Final payment	On practical completion and sign-off	10–15%

Issue a separate invoice for each stage, numbered sequentially (INV-0041, INV-0042, INV-0043, INV-0044). The final invoice shows all previous stage payments deducted from the total, with the remaining balance due.

VAT on Deposit Invoices

If you are VAT-registered, VAT applies to deposits in the same way as to the full invoice. The VAT tax point (when VAT becomes due) is the earlier of:

The date you receive the deposit payment
The date you issue the deposit invoice

This means if you issue a deposit invoice in June but it is paid in July, VAT is due in your June VAT period (when the invoice was issued). On the final invoice, show VAT on the total job value and deduct the VAT already accounted for on the deposit. If this is complex, your accountant can show you how to record it correctly.

How to Do This in TraderInvoice

TraderInvoice makes the deposit workflow straightforward:

Send a voice quote first

Speak your scope and price. The customer gets an acceptance link. Once they accept, you have a signed-off price — the foundation of a clean deposit arrangement.

Create the deposit invoice

Create an invoice for the deposit amount, referencing the quote number and total job value. Label it clearly as a deposit.

Create stage invoices as work progresses

For staged projects, create each stage invoice as the milestone is reached. Keep numbering sequential.

Issue the final balance invoice

Show the full job total with all previous payments deducted. The customer sees a clear, transparent record.

Handle deposits and staged invoicing by voice

TraderInvoice is free for up to 5 invoices/month. Starter plan (£29/month) includes quoting with customer acceptance — the first step in any proper deposit workflow.

Start Free Quote Template Guide →

Frequently Asked Questions

Should a plumber ask for a deposit before starting work?: Yes — for any job with significant material costs or duration, a deposit is standard and strongly advisable. It protects you if the customer cancels after you have ordered parts, and it demonstrates the customer is serious. A 25–50% deposit is the norm for bathroom fits, boiler installations, and larger plumbing projects. For routine call-out jobs, payment on completion is standard.
What should a plumber's deposit invoice include?: A deposit invoice should include all the standard invoice elements (your business details, customer details, unique invoice number, date) plus: a clear description of the job the deposit relates to, the total agreed quote amount, the deposit percentage and amount, your bank details for payment, and the expected start date. Label it clearly as 'Deposit Invoice' so it cannot be confused with the final invoice.
How do I show a deposit on a plumber's final invoice?: List the deposit as a line item deduction on the final invoice. For example: 'Less deposit paid 15 June 2026 (Invoice DEP-0012): −£500.00'. The final invoice should show the total job value, then the deposit deduction, then the balance due. This gives the customer a clear, transparent record of what they have already paid and what remains.
Is VAT charged on a plumber's deposit invoice?: Yes, if you are VAT-registered. VAT is due on deposits at the time the deposit is paid (the tax point is the earlier of the date you receive the payment or the date you issue the deposit invoice). Apply VAT at the relevant rate to the deposit amount, just as you would to the full invoice.
What happens if a customer cancels after paying a deposit?: If a customer cancels after you have commenced work or ordered materials, you are generally entitled to keep the deposit to cover your costs and losses — provided your terms and conditions state this clearly. If no work has been done and no materials ordered, the right to keep the full deposit is less clear under consumer law. For large deposits, state your cancellation policy explicitly in your quote and in any written agreement.