Unpaid Invoice Recovery: From Internal Efforts to Professional Collection

An unpaid invoice starts as an administrative matter and becomes a financial one remarkably quickly. At day 30, it’s an overdue receivable. At day 60, it’s a cash flow problem. At day 90, it’s a potential write-off that your CFO will ask about at the next quarterly review. The trajectory is predictable, and the intervention points are well-established — what varies is whether businesses act on them or hope the problem resolves itself.

The Internal Recovery Phase (Days 0–60)

Most unpaid invoices are recoverable through internal action if the process is structured and timely.

The Professional Recovery Phase (Days 60–120)

For invoices owed by Spanish companies, professional recovery means engaging a Spain-based collection agency that can apply local pressure the debtor can’t ignore.

Amicable collection. A locally-based agent contacts the debtor in Spanish: phone calls, formal demands via burofax, field visits to the debtor’s premises. The agent understands Spanish commercial law, knows the debtor’s obligations under Ley 15/2010, and can reference specific legal consequences. This phase resolves 70–85% of commercially viable debts on no-win, no-fee terms (5–15% commission).

Pre-legal attorney demand. A formal demand from a Spanish attorney, sent via burofax, citing specific legal provisions and naming the court procedure that will follow. Cost: €300–€800. Resolves a significant additional proportion of invoices that resisted amicable collection.

The Legal Recovery Phase (Days 90+)

For documented invoices where the debtor remains unresponsive or refuses to pay, the monitorio payment order is the standard legal tool. Fast-track procedure, 30–45 days to enforceable judgment for uncontested claims, costs of €1,000–€5,000 depending on invoice amount. For contested invoices, full civil proceedings (juicio ordinario or juicio verbal) provide judicial resolution over a longer timeline (6–18 months).

Documentation That Maximises Recovery Probability

Essential: signed contract or purchase order, issued invoice(s), proof of delivery or service completion (delivery notes, sign-offs, completion certificates).

Valuable: correspondence confirming the debtor’s acceptance of goods/services, any acknowledgment of the debt (partial payment, email requesting more time, payment plan discussion), formal demands sent during internal collection (with delivery proof).

Helpful: debtor’s filed accounts from the Registro Mercantil, credit reports, prior payment history.

FAQ

Should I stop supplying the client while pursuing the unpaid invoice?

This is a commercial judgment, not a legal one. Continuing to supply creates additional exposure. Stopping supply may damage the relationship (if you want to preserve it) or may accelerate the debtor’s engagement (if they need your products). Most creditors stop further supply once an invoice is 60+ days overdue and actively in collection.

Can I recover statutory interest on the unpaid invoice?

Yes. Under Ley 15/2010, statutory late payment interest (ECB base rate + 8 percentage points) accrues automatically from the day after the contractual payment deadline. You don’t need a contract clause to claim it. Many overseas creditors don’t claim statutory interest, leaving significant money on the table. Your collection agency or attorney should include the interest calculation in every demand.