Most advice on unpaid invoices stops at "send a follow-up email." That's step one of a much longer process — here's the full path, in order, so you're not improvising when a client actually stops paying.
Weeks 1–2: Assume good faith
A short, friendly reminder referencing the specific invoice number and due date. Most non-payment at this stage is genuinely an oversight — a missed email, an accounts-payable queue, someone on vacation. Don't escalate the tone yet; you're just re-surfacing the request.
Weeks 2–4: Get firmer, get specific
Reference your payment terms explicitly, including any late fee stated in your original agreement. Ask directly: "Is there an issue with the invoice I should know about, or can I expect payment by [date]?" This question does real work — it forces a response, and it surfaces disputes (wrong amount, work quality complaint) that need a different conversation than a payment reminder.
Week 4+: Send a formal demand
A short, unambiguous letter (email is fine, but keep it separate from your regular correspondence) stating the amount owed, the original due date, and a firm deadline — typically 7–10 days — after which you state plainly what happens next: pausing future work, late fees applying, or referral to collections. This isn't about sounding aggressive; it's about creating a clear paper trail, which matters a great deal if you end up in the next step.
Beyond 30–60 days: escalate for real
- Small claims court — for amounts within your jurisdiction's limit (often $5,000–$10,000+ depending on location), this is cheaper and faster than most people expect, and a documented invoice trail is exactly the evidence you need.
- Collections agency — typically takes 25–50% of what's recovered, worth it mainly for larger amounts where you have no time to pursue it yourself.
- Write it off — genuinely the right call sometimes. Chasing a small invoice for months can cost more in time and stress than the invoice is worth. Many jurisdictions let you deduct bad debt at tax time, which softens the loss.
What makes every step of this easier
A clean invoice trail: numbered invoices, stated due dates, stated late fees, and a record of every follow-up. None of the escalation steps above work well without that paper trail already in place — which is really an argument for consistent invoicing habits before a client goes quiet, not after.