Invoice Chaser

Chasing money is the job nobody does, because it is awkward and because it always seems like it can wait another week. This does it on a timetable instead, which is the only thing that reliably works.

You keep your invoices on a Google Sheet: who, how much, when it was due, and whether it is paid. Once a day the script looks down that list and sends whatever is due to be sent. A gentle heads-up three days before the due date. A note on the day. Then a first, second and final chase at seven, fourteen and thirty days past due, each one a little firmer than the last. You choose those intervals and you write the wording.

It never sends the same reminder twice, whatever happens - not if the script runs twice, not if you press Run yourself, not if you reinstall it. The moment you put Paid in the status column, that invoice is left alone for good.

It starts in test mode, so the first few days of messages come to you rather than to your customers. Read them, change the wording until it sounds like you, then turn test mode off.