12 Common Invoice Mistakes That Delay Your Payment
Missing PO numbers, vague descriptions, wrong tax rates — the errors that push invoices to the bottom of the pile, and how to avoid them.
Daniel Okafor 6 min read
The list
- No unique invoice number. Impossible to reference or reconcile.
- Missing purchase order number. Enterprise systems will reject it outright.
- Vague line descriptions. "Consulting" invites questions; questions cost weeks.
- No due date. "Soon" is not a term.
- Wrong legal entity. Bill the company on the contract, not the trading name.
- Maths that does not add up. Always let the tool calculate totals.
- Incorrect tax rate or missing tax number. Blocks the client's own reclaim.
- No payment instructions. Do not make clients ask for your bank details.
- Editable file formats. Send PDF.
- Sending to the wrong inbox. Find accounts payable early.
- Invoicing late. You slip a whole payment cycle.
- No follow-up system. Unchased invoices are paid last.
The fix
A structured template eliminates eight of the twelve automatically. Our free invoice generator validates totals in real time and keeps required fields visible.
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Daniel Okafor
Daniel Okafor writes about invoicing, cash flow and small-business finance for Invoice Creator. Every guide is reviewed against the fields our own invoice generator produces, so the advice matches the tool.
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