How I built a free invoice chasing system (no SaaS needed)

Most freelancers handle late invoices one of two ways: Ignore it and hope the client pays eventually Send a passive-aggressive email that damages the relationship Both are terrible. Here's a better system. The 4-stage escalation framework I built this based on UK late payment law and what actually works: Stage 1: Friendly reminder (1-7 days overdue) Hi [name], just a quick one — invoice #X for £Y was due on [date]. Could you confirm when payment will be processed? Happy to resend if needed. Key: assume it's an oversight. No accusations. Stage 2: Firm follow-up (8-14 days) Hi [name], following up on invoice #X (£Y), now [X] days overdue. Could you let me know a specific date I can expect payment? I've attached the original invoice for reference. Key: ask for a specific date , not just "when you can". Stage 3: Formal notice (15-21 days) Now you mention the law: Under the Late Payment of Commercial Debts (Interest) Act 1998, I'm entitled to charge statutory interest of 8% + Bank of Englan