Guide updated 11 July 2026
The month's documents, without chasing anyone
Every tax advisory firm knows the 18th: half the clients have not sent anything yet, and what does arrive comes through five different channels, with crooked photos and the odd duplicate invoice. The problem is not the client: it is that sending is still harder than not sending.
One place, not five
Email, WhatsApp, a shared folder, by hand, through the accounting software… Each channel is one more place to look and one more chance for something to get lost. What works is a single link per client that asks for no account or password and tells them immediately whether what they uploaded has been received.
Check before opening
An invoice whose total is not the base plus VAT, a NIF with a wrong check digit or an invoice without a number are discovered today when posting, weeks later. If the check is done at upload, the client can fix it on the spot and the firm opens the submission already knowing what to look at.
What the GDPR says
The advisory firm is a processor of its clients' data (art. 28 GDPR) and must be able to show that it protects it. Invoices carry third parties' names, tax IDs, addresses and bank accounts. A personal chat or an email with attachments that stays for years in a mailbox is not the measure an inspector expects to see; an encrypted channel, with deletion and a log of what was received, is.
The reminder you do not have to write
An automatic reminder, with the same link, to whoever has not yet sent anything by mid-month recovers most of the delays without anyone at the firm having to write an email.
How the AIM PAPYR mailbox does it
Each client receives their link and uploads the month's documents without signing up. Each document is checked with fixed rules (arithmetic, NIF, number) and the firm receives a notification and an Excel with whatever does not add up at the top, alongside the originals. Documents are encrypted for a key that only the firm's browser holds, so not even we can open them, and they are deleted when opened, or after 30 days. Free for up to 3 clients.
Frequently asked questions
Does the client need to sign up?
No. They open the link, drop the documents and that is it.
What happens if I lose the key?
Whatever is pending to be opened cannot be recovered: that is why the panel offers to save a copy of the key and load it in another browser. Your client can always send it again.
Do the documents go through email?
No. Email only tells you that something new has arrived; the documents are opened from your panel.