Late Fees

Apply legally valid late payment surcharges on overdue B2B invoices — the €40 statutory recovery fee (Art. 8.1 Law 3/2004), percentage surcharge, or the statutory commercial late-payment rate.

Overview

Frihet calculates late fees on commercial B2B invoices that remain unpaid past their due date (when the legal requirements of Art. 6 of Law 3/2004 are met; consumer B2C operations are excluded under Art. 3.2.a). It supports three calculation methods:

• Fixed flat fee per invoice: e.g., the €40.00 statutory collection-cost compensation under Art. 8.1 of Law 3/2004.
• Annual percentage: an agreed annual rate applied per day of delay on the outstanding balance.
• Statutory late-payment rate: Frihet applies 8% per year by default, not the rate published in the BOE; to claim the exact statutory rate, use the resolver or set the percentage.

Applying the late fee creates a separate late-fee charge linked to the original invoice, which is not modified.

Quick start

1. Go to Settings → Late Fees.
2. Turn on Enable late fees and choose your calculation method (Fixed amount / Annual percentage / Legal interest rate).
3. On any overdue B2B invoice, click Apply late fee. You can also use the AI assistant (apply_late_fee).

Interactive Late-Payment Calculator & Resolver

Use the Interactive Unpaid Invoice Resolver to simulate exact multi-semester BOE interest (H1 2026 at 10.15% + H2 2026 at 10.40%), the €40 compensation fee, and 4-stage dunning templates.

Reference

• REST API: POST /v1/invoices/{invoiceId}/late-fee — see API reference. The API and the MCP tool apply a simple 8% annual rate, or the amount you send, without using your configuration
• MCP tool (@frihet/mcp-server): apply_late_fee — see MCP reference
• Related guide: How to collect overdue invoices without chasing clients
• Settings path: Settings → Late Fees