When invoices sit unpaid, the instinct is to assume the client will not pay. Far more often, nobody has looked at the invoice, and the reason it has not been looked at is something on your side.
The seven reasons invoices sit unpaid
- No purchase order number. The invoice cannot be matched, so it waits.
- Wrong entity name. The finance system has no supplier by that name.
- Sent to the wrong person. Your contact is not accounts, and forwarding it is not their job.
- A required field is missing. Most often a VAT number.
- The amount does not match the quote or PO. Any variance stops it.
- It arrived after their cut-off. Many companies run a monthly payment run with a deadline.
- They genuinely cannot pay. Real, and the least common of the seven.
Six of those are process failures. Five of the six are yours to fix before you send.
Diagnose before you chase
A chase email that says following up on the below gets you nothing when the answer is a missing PO number. Ask a question that identifies the blockage instead:
Could you confirm invoice INV-0148 was received and matched? If a PO number is needed I will reissue with it today.
That sentence offers the most likely fix in advance, which is why it gets a reply where a general reminder does not.
Payment runs
Many companies pay on a cycle, not on your due date. If a client runs a payment run on the 25th with invoices required by the 15th, an invoice sent on the 16th waits five weeks regardless of your terms.
Ask any new corporate client two questions at onboarding: when is your payment run, and what is the cut-off? Then invoice to land before it. This is the single highest-return question in the whole process, and almost nobody asks it.
What to fix at your end
| Fix | Effect |
|---|---|
| Ask for the PO number at quotation stage | Removes the most common blockage |
| Capture the client's legal entity name | Removes the second |
| Ask who invoices should go to | Removes the third |
| Invoice the day work completes | Catches the current payment run |
| Attach a statement on any follow-up | Reframes it as an account, not a single document |
Common questions
How long before I chase?
The day after due. Waiting a week turns an oversight into a decision.
Should I phone or email?
Email first, so there is a record, then phone if there is no reply within a few days.
Is it worth asking about payment runs?
It is the highest-value question you can ask a new corporate client, and it takes one line in an email.
Capture client details and PO numbers once, and every invoice carries them.
Create your invoiceDisclaimer: This content is for general information only and does not constitute legal, tax, accounting or financial advice. Always confirm important requirements with SARS, the relevant authority or a qualified professional.
