The overdue invoice sits there, and two bad voices start up. One says "let it go, the relationship matters". The other says "post about it, that will move them". Both are wrong. Money arrives, and reputations survive, on a ladder climbed one rung at a time, in writing.
Rung 1: the warm chase (first two weeks)
Most late payments are process: a PO stuck in an approval queue, a finance cycle that runs 45 or 60 days. One clear, dated reminder with the invoice attached often clears it. Warm, brief, on the record. One nudge a week is plenty.
Rung 2: escalate inside the company (weeks two to four)
Move up one rung at a time: your contact, then the marketing head, then accounts payable. Email beats DM because it builds the paper trail everything later stands on. If an agency sits in the middle, ask in writing for the PO number and the payment status; unless your contract says pay-when-paid, the agency owes you regardless.
Rung 3: the formal demand letter (about a month)
A demand letter on your letterhead, sent by email and courier, changes who reads your case: it moves from a marketing inbox to finance. The strong version cites real levers: MSME interest if your Udyam registration predates the deal, the GST input-credit reversal on invoices unpaid past 180 days, the TDS certificate they owe you. Facts, amounts and dates. No adjectives.
Rung 4: the free government route (six weeks and beyond)
If you are Udyam-registered, MSME Samadhaan lets you file a delayed-payment case online, free, no lawyer. Interest compounds in your favour and a buyer must deposit 75% of an award to challenge it; often the filing alone triggers payment. Know what you are choosing: a formal case usually ends that working relationship. By this rung, the trade is usually worth it.
What we deliberately do not recommend
Public call-outs before the formal remedies are exhausted, threats of any kind, or police complaints for what is a civil debt (courts routinely quash FIRs used as recovery pressure). Never say "pay or I will post": a monetary demand tied to a threat to publish walks into extortion territory. Your leverage is the law and the paper trail, and it is more than enough.
Creator Kamai's Get Paid tool runs this ladder from your own records: it drafts the reminders, generates the demand letter with the right legal paragraphs, and walks the MSME filing step by step. Information and drafts, not legal advice; for large amounts, an hour with a lawyer is money well spent.