kertalasku

Kertalasku is a Finnish invoicing term describing an invoice that covers a single payment for a defined set of goods or services, rather than a recurring billing period. It is commonly used for one-off purchases, installation or activation fees, project work, or final settlements when a contract ends.

A kertalasku typically contains the standard elements of an invoice: the issue date and a unique invoice number, the seller’s and customer’s contact details, a clear itemization of charges with descriptions, quantities, unit prices, and any applicable VAT. It also shows the subtotal, the total amount due, payment terms, and the due date. Additional information may include invoicing or reference numbers, shipping details, and instructions for payment methods.

Issuance and timing depend on the transaction. A kertalasku is usually issued after the service is delivered or a milestone is reached, or when a one-off product is supplied. The customer is expected to settle the amount by the specified due date, subject to the agreed payment terms, which may specify late fees or interest for overdue payments.

In practice, kertalasku contrasts with recurring invoicing models such as monthly subscriptions or usage-based bills. It is commonly used in business-to-business and business-to-consumer transactions where charges are not expected to repeat on a regular schedule. In digital and administrative workflows, kertalasku is supported by standard invoicing software and may be issued as an electronic document (e-invoice) in line with local regulations.