A client won't pay your invoice? Here's exactly what to do

First, breathe. Most unpaid invoices are not fraud; they are forgetfulness, a lost email, or an internal approval stuck somewhere. Panic emails make it worse. A calm, escalating process recovers the large majority without ever getting to anything ugly.

Step 1: The neutral nudge (a few days overdue)

Assume good faith. “Hi, just flagging invoice #1041 was due on the 3rd, the details are below. Let me know if you need anything to process it.” No accusation, easy to action.

Step 2: The firm follow-up (about a week over)

Now name the gap directly but politely. “This is now a week past due. Could you confirm when I can expect payment, or let me know if there is a problem with the invoice?” You are giving them a clear prompt and a chance to surface any issue.

Step 3: The clear ask (two weeks over)

Be direct and reference your terms. “This invoice is now 14 days overdue. Please arrange payment by [date]. If there is a dispute, let me know so we can resolve it.” Keep it professional; it may need to be a record later.

Step 4: If it is still unpaid

Pause further work, send a final written notice with a deadline, and know your options: late-payment interest (in the UK, the statutory right exists for B2B), a letter before action, or small-claims/mediation for larger sums. You rarely need these, but saying “next step is a formal notice” often resolves it.

How to never be here again

Two habits prevent almost all of this:

Automate the reminders. The cadence above only works if it actually goes out. Set it once and let it run, so politeness is consistent and you are not the one chasing.
Deliver after payment, not before. For final files, hand them over behind a link that unlocks once the invoice clears. No more delivering the work and then hoping.