Invoice format for small businesses (with free generator)

The first "real" invoice most small businesses send is copied from an old one someone emailed them in 2015. It usually works — until a company client's accounts department bounces it for a missing detail, and payment waits another month. Here is what an invoice needs, and the fastest way to produce one.

What every invoice must contain

• The word "Invoice" and a unique invoice number (INV-0001, INV-0002 — sequential, never reused).
• Your details: business name, address, phone — and your business registration or tax ID (VAT number, EIN or equivalent) if you have one.
• The customer's name and address — company clients need this exactly right for their records.
• Date of issue and, if you give credit, the due date (write the actual date, not just "Net 30").
• Itemised lines: description, quantity, unit price, line total — then subtotal, any discount or tax, and the grand total with its currency.
• How to pay: bank details or a payment link. Missing payment details are the number-one self-inflicted payment delay.

Common mistakes that delay payment

• Reusing invoice numbers, which makes reconciliation impossible and audits unpleasant.
• Vague line items ("work done — $450") that invite queries instead of payment.
• No due date, which the customer reads as "whenever".
• Sending a photo of a handwritten bill to a corporate client.

The fast way: generate it

Duqit's free invoice generator produces a clean, correctly-structured invoice in your browser — fill in the details, print or save as PDF. Free, no sign-up, nothing stored.

When you outgrow one-off invoices

The generator is perfect for occasional billing. When invoicing becomes daily, you want numbering that increments itself, customer details that fill themselves in, unpaid invoices flagged in a list, and a bill the customer opens from a WhatsApp link. That is Duqit Business POS — invoicing, inventory and customer records for $2.99/month after 3 free months.