Send a friendly reminder the day after the due date. Most late payments are forgotten, not refused. If no response, escalate over 30 days through 4 stages: friendly reminder → firm reminder → final notice with late fee → formal demand. This guide includes ready-to-use email templates for each stage, when to escalate to legal action, and how to prevent late payments in the first place.
The day after the invoice due date — not a week later. Sending the reminder on day 1 establishes that you track payments closely and recovers most 'forgotten' invoices within 48 hours.
Only if the late-fee policy was on the original invoice or in your contract before it was sent. You can't add a fee retroactively.
Generally yes, especially if the unpaid invoice is more than 30 days overdue. Continuing to work for a non-paying client multiplies your exposure.
Usually after 60-90 days of no response and a formal demand letter has been ignored. Small claims is cheap ($50-$200 filing) and you don't need a lawyer.
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