Plumber Invoice Template: What to Include for Professional Billing

A well-crafted invoice does more than request payment—it reinforces your professionalism, reduces questions and disputes, and helps you get paid faster. For plumbers, specific details matter.

This guide covers exactly what your plumbing invoices should include and common mistakes to avoid.

Essential Invoice Elements

Your Business Information

At the top of every invoice:

• Business name - Your trading name or company name
• Logo - If you have one, use it
• Address - Your business address
• Phone number - How customers can reach you
• Email - For correspondence
• Gas Safe / certification numbers - Essential for compliance
• Insurance details - Public liability policy number (optional but builds trust)
• VAT number - If VAT registered

Customer Information

• Customer name - Person or business you're billing
• Service address - Where the work was performed (may differ from billing address)
• Billing address - Where to send the invoice
• Contact number - For any queries

Invoice Details

• Invoice number - Unique identifier for tracking (e.g., INV-2025-0042)
• Invoice date - When the invoice is issued
• Due date - When payment is expected (e.g., "Due within 14 days")
• Payment terms - Your standard terms

Line Items: The Heart of Your Invoice

This is where many plumbers go wrong—either too vague or too confusing. Aim for clear, itemised details.

Good Practice: Separate Labour and Materials

Labour:

• Description of work performed
• Time spent (hours or days)
• Rate applied

Materials:

• List of parts and materials used
• Unit costs
• Quantities

Example:

Why Itemisation Matters

• Transparency - Customers see exactly what they're paying for
• Trust - No hidden charges or unexplained totals
• Fewer disputes - Clear breakdowns reduce questions
• Tax records - Easier for both you and the customer

Additional Information to Include

Job Reference

Link the invoice to the original quote or job number. This helps both you and the customer track the work.

Work Description

A brief summary of what was done:

"Attended property to investigate reported leak under kitchen sink. Identified failed compression fitting on waste pipe. Replaced fitting and section of damaged pipe. Tested system—no leaks detected. Advised customer on waste disposal practices to prevent future blockages."

This creates a record and demonstrates the value you provided.

Warranty Information

If your work carries a guarantee, state it clearly:

"Workmanship guaranteed for 12 months from date of completion. Manufacturer warranties apply to installed products."

Payment Methods

Make it crystal clear how customers can pay:

• Bank transfer (include sort code, account number, reference)
• Card payment via link
• Cash or cheque (if you accept these)

Always include direct payment links if possible—making payment easy dramatically reduces payment times.

Common Invoicing Mistakes

Being Too Vague

❌ "Plumbing work - £300"

✅ "Repair leaking tap in ground floor bathroom: replaced ceramic disc cartridge, tested operation. Labour 1.5 hrs @ £55/hr. Parts: Bristan cartridge £18"

Forgetting Due Dates

Without a clear due date, customers don't know when to pay. "Due on receipt" is fine, but specific dates (e.g., "Due by 15 January 2025") are clearer.

Not Including Payment Details

Every invoice should have complete payment information. Don't make customers search for your bank details or call to ask how to pay.

Handwritten or Messy Invoices

Professional invoices build trust. A scribbled note on a piece of paper doesn't inspire confidence—even if your plumbing work is excellent.

Delayed Invoicing

Send invoices immediately after completing work—ideally before leaving site. Delays lead to forgotten details and slower payment.

Digital vs Paper Invoices

Benefits of Digital Invoicing

• Faster delivery - Email arrives instantly
• Payment links - One-click card payment
• Automatic reminders - No manual chasing
• Record keeping - Searchable history
• Environmental - No paper waste
• Professional - Modern expectations

When Paper Still Works

Some customers (particularly older customers) prefer paper. If so, still use professional printed invoices—not handwritten notes.

Invoice Numbering Systems

Keep your invoice numbers consistent and logical:

Sequential: INV-0001, INV-0002, INV-0003 Year-based: INV-2025-001, INV-2025-002 Customer-based: SMITH-001, SMITH-002

The key is consistency. Gaps in numbering can raise questions if you're ever audited.

Automating Your Invoicing

Modern invoicing software can:

• Pre-fill customer details from your database
• Calculate totals including VAT automatically
• Send reminders when invoices are overdue
• Track payment status so you know who's paid
• Generate reports for accounting and tax

For plumbers doing multiple jobs per week, automation saves hours of admin time.

Template Quick Reference

Every plumbing invoice should include:

Header:

• Your business name and logo
• Your contact details
• Registration/certification numbers
• Customer name and address
• Service address (if different)

Details:

• Invoice number
• Invoice date
• Due date
• Quote/job reference

Line Items:

• Labour description and time
• Labour rate and total
• Materials itemised
• Subtotal, VAT, and total

Footer:

• Work summary
• Warranty information
• Payment methods and details
• Payment link (if using digital)

Conclusion

Professional invoicing is part of professional plumbing. A clear, detailed invoice completes the job properly, gets you paid faster, and builds your reputation as a tradesperson who takes their business seriously.

If you're still using handwritten invoices or basic templates, it's time to upgrade. Your work deserves better presentation—and your bank account will thank you.

Ready for professional plumbing invoices? Try Cadobook with trade-specific templates designed for plumbers.