Whether it is to prove access to a warranty or to justify a tax expenditure, it is necessary to keep a significant number of invoices.
The method of saving doesn’t really matter: digitally or in hard copy, but it’s important to be able to guarantee the authenticity of the origin and the integrity of the content of those invoices. You will also need to be able to guarantee that those invoices have been unaltered between the moment that you have received them and the end of the retention period.
Always be sure to keep the invoice itself and not an e-mail or a link to the document, as you would run the risk of having the link disabled.
You will find more info on the SPF Finances [FPS Finance].
Retention period for invoices
The FPS Finance recommends keeping all invoices and copies of invoices for approximately seven years, from January 1st of the year following their issue date. Depending on the documents to be kept, the recommended period can range from 3 to 10 years.
Which invoices do you need to keep ?
Whether it concerns the retention of telephone-, water-, electricity, gas-invoices or those related to the purchase of an electrical household appliance, a jewel or an object or service for which you may need to justify or document the purchase or show proof for warranty purposes.
See also https://www.izimi.be/faqs/combien-de-temps-garder-ses-factures