Purchase deduplication

Aikount enforces a hard rule: a purchase invoice must never be duplicated. It doesn't matter if you drop the same PDF twice, the expense arrives through both the importer and AI ingest, or a supplier resends the same invoice: it enters only once.

Warning. A duplicate purchase corrupts three things at once: expenses (it inflates your totals and your result), input VAT (you deduct the same 472 twice on Modelo 303) and bank reconciliation (two entries fighting over a single bank movement). It's the most expensive mistake to fix afterwards.

By invoice identity, never by file#

Deduplication is done by the invoice's identity, not by the identifier of the source file, the PDF or the spreadsheet row. Two criteria:

1. Supplier + supplier invoice number. If a purchase already exists for that supplier with that invoice number, it's the same one. This is the primary criterion.
2. Fallback by total + date ±7 days. When the invoice number is unavailable or unreliable, Aikount compares the total amount and the document date within a seven-day window.

Deduplicating by the file id (or Drive id, or row index) is a classic mistake: the same invoice can arrive under two different files and create a duplicate. That's why Aikount always looks at what truly identifies the invoice.

The same supplier across two contacts#

A common risk is having the same supplier split across two contacts (for example, after a bulk import with bad data). Deduplication covers this by cross-checking on normalized name or shared VAT number, so the same invoice doesn't slip through twice just because the supplier is duplicated. More detail in Suppliers.

Invoices with multiple charges#

Watch out for multi-charge statements that share a single invoice number (for example, threshold prepayments from an ad provider, or multiple lines from a hosting provider). There, one number corresponds to several real charges: they are not collapsed into one. They are modeled as a single invoice reconciled against the different bank movements.

What you do#

In practice, almost nothing: deduplication is automatic. If you try to register something Aikount recognizes as already existing, no duplicate is created. If they really are two distinct invoices that happen to share a total and date, check the supplier invoice number so each keeps its own identity.

Related#

• Import invoices with AI — the ingest flow that already deduplicates for you.
• Suppliers — how the same supplier across two contacts can create duplicate risk.