Nineinvoicemistakesthatdelaypayment

Every one of these is invisible to the person sending the invoice and immediately obvious to the person trying to pay it.

6 minute read · Updated

Short answer

The mistakes that delay payment most are: no purchase order or reference number, a due date written as “Net 30” rather than a date, a single vague line item, missing payment details, sending only to your contact rather than to accounts payable, an inconsistent invoice number series, the wrong GST split for the place of supply, a PDF that is an image rather than text, and a file named something like invoice-final-2.pdf. All nine are fixed at the moment you create the invoice, and none of them can be fixed by chasing.

The nine

No PO or reference

In any company with procurement, an unmatched invoice never enters the payment run. It stops with someone who cannot approve it and does not know who can.

“Net 30” instead of a date

An instruction to do arithmetic, not a deadline. Accounts payable systems key on dates.

One line saying “services rendered”

Nothing the approver can verify, so they escalate it to someone more senior, who is busier.

No payment details on the document

If the bank details live in the covering email, they are gone the moment the PDF is filed.

Sent only to your contact

The person who commissioned the work rarely pays for it. Send to them and to accounts payable.

An inconsistent number series

Duplicates and gaps invite questions. Under GST the series must be consecutive and unique for the financial year.

The wrong GST split

CGST/SGST where it should be IGST, or the reverse. The customer's credit is affected, so they will send it back.

A PDF that is an image

Cannot be searched, copied from, or read by the software processing it. Scanned or screenshotted invoices stall.

A filename like invoice-final-2.pdf

It has to be findable in a folder of four hundred. Name it by type, number and client.

The three that cost the most

If you only fix three, fix the PO number, the due date and the itemisation. Together they account for most of the delay in most invoices, and all three are decided before you press download.

The PO number is worth a particular note because it is the only one you cannot fix afterwards without reissuing. Ask for it at the point the work is agreed. If the answer is “we don't use POs”, get that in writing from someone in finance, because the person telling you often does not know.

The rupee sign nobody checks

A quieter one, worth its own mention: a surprising number of invoice tools print a box, a question mark or “Rs.” where the ₹ should be. It happens because the font embedded in their PDF has no glyph for it — the standard PDF fonts are Western-encoded, and ₹ is not in that set.

It looks careless on a document that is asking for money, and on a large figure it introduces genuine ambiguity. Download one test invoice with a rupee amount and look at it before you trust any tool with a real one.

The reference

What to put on an invoice

The fields every invoice needs, the four omissions that hold payment up, and how to word payment terms so an invoice does not sit in an inbox for a month.

Make one now

Free, no sign-up, and nothing you type leaves your browser.

Questions people ask

Almost always because the invoice cannot be matched to something already approved — usually a missing purchase order number — or because a line item does not correspond to anything the approver recognises. Genuine disputes about the work are far rarer than administrative mismatches, which is why itemising clearly is worth more than any amount of chasing.

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