How to Collect Payment on Site as a Gas Engineer

Every invoice you leave unpaid when you walk off site is a debt that requires chasing — time, awkwardness, and uncertainty. On-site payment collection eliminates this entirely. You leave with the job complete and the money in your account (or your card reader).

For domestic work especially, on-site payment is both expected and preferred by most customers. They've just had a boiler installed or a gas safety check done — they're relieved, it's complete, and paying immediately feels natural. The customer who cheerfully hands you a card on the doorstep is the same customer who ignores a bank transfer reminder three weeks later.

For many gas engineers, moving to on-site payment for routine and smaller jobs is the single biggest improvement to cash flow they can make, with no cost other than a portable card reader.

Portable card readers are inexpensive, reliable, and accept all major card types. The main options for UK gas engineers:

• SumUp Air: One-off cost of around £29. Transaction fee of 1.69% on card-present payments. Connects to your phone via Bluetooth. Accepts contactless, chip-and-pin, and Apple/Google Pay. No monthly fee. The most popular choice for sole trader tradespeople in the UK
• Square Reader: Similar pricing — around £19 for the basic reader. 1.75% transaction fee. Clean interface and good reporting through the Square app. Also accepts contactless and chip-and-pin
• iZettle (Zettle by PayPal): Around £29. 1.75% transaction fee. Good integration with PayPal and some accounting systems. Solid mobile app
• Worldpay: Enterprise card machines with monthly fees — more appropriate for businesses with high transaction volumes where a lower per-transaction rate justifies the monthly cost. Not necessary for most sole traders

For a typical gas engineer doing 3–5 jobs per day at £100–£300 each, the 1.69–1.75% fee is negligible (£1.69–£5.25 per £100 transaction). The cost of using a card reader is far less than the cost of chasing unpaid invoices.

Many job management platforms (Jobber, Commusoft, Tradejoy) allow you to generate and send an invoice directly from your phone while on site, with a built-in payment link. The customer receives an SMS or email with a link, taps it on their phone, and pays by card in under 60 seconds — without you needing to carry a physical card reader.

This approach works particularly well for customers who prefer digital over physical card readers (more common in urban and tech-savvy demographics). Payments are typically processed within 1–2 business days.

The key is generating the invoice before you leave site. If you wait until you're back at the van or at home, the customer has already mentally moved on — they're less focused, more likely to defer. Hand them the invoice (or send it immediately) while standing in their hallway, and the request for payment feels natural and immediate.

Many gas engineers feel uncomfortable asking for payment on site, particularly from domestic customers. This discomfort often stems from British social norms around money. But customers expect to pay — the awkwardness is usually in your head, not theirs.

A simple, natural script:

"Right, that's all done — [brief explanation of what was done, e.g. the boiler's running perfectly and I've commissioned it and set the programmer for you]. Here's your Gas Safe certificate and the manufacturer warranty card. The total is £[amount] — do you want to pay by card now or would you prefer I send you an invoice to pay by transfer today?"

Two options, both involving payment. Not "I'll send you an invoice" (which invites delay) but "card now or transfer today." Most customers choose card on the spot because it's the path of least resistance.

For customers who feel uncomfortable with on-site payment for larger sums, sending the invoice immediately by email or text with a payment link while you're still packing up your tools is a good alternative. The invoice arrives while you're still there, feels immediate, and usually results in same-day payment.

Despite best practices, some customers will not pay on the day. Have a clear process for what happens next:

• Day 1: Automated invoice reminder (if using software) or a brief text: "Hi [name], just a reminder that the invoice for today's work is attached — payment by bank transfer to [details] or use the payment link in the email."
• Day 7: A phone call. Friendly, not confrontational: "Hi [name], just calling about the invoice from [date]. Is everything okay with the work? I noticed the payment is still pending."
• Before the next visit: For any customer with an outstanding invoice, don't attend a follow-up visit until the current invoice is cleared. Make this a policy — "I'm afraid I can't book a follow-up visit while there's an outstanding invoice. Once that's cleared, I'll be happy to arrange your next appointment."