Invoice generator
for heating engineers

An invoice should include your business name, address, and contact details, the customer name and address, a unique invoice number, issue date and payment due date, a line-by-line breakdown of work done and materials, subtotal, VAT if applicable, total due, and your bank details for payment. This generator covers all of it.

Same day is best. Tradespeople who invoice within 24 hours of completing work get paid significantly faster than those who wait. This generator makes it easy to send one before you've even left the job.

Yes, completely free, no sign-up required, no watermark on the invoice. Clara built this tool because heating engineers told us getting paid on time is one of the biggest headaches in the trade. Use it as much as you like.

Start with a polite follow-up referencing the invoice number and due date. If that fails, send a formal letter before action. Your invoice includes statutory late payment interest terms, which gives you a legal basis to charge interest on overdue amounts. For persistent non-payment, small claims court is a straightforward option for amounts under $10,000.