What is a digital mail carrier?

Certified Delivery Channel for e-Invoices

Digital Postman is a certified channel for the secure delivery of e-invoices between the sender and the recipient.

How It Works

1.

Choose the Flowis Digital Mail Carrier

2.

If you are the recipient, please confirm it on the FS website

3.

Send and receive e-invoices

The Peppol Network

The entire system operates onthe decentralizedPeppol network, which is managed by the European Commission. It defines technical standards, security requirements, and organizational rules.

Start the video and find out
how e-invoicing works

Flowis Digital Postman simplifies e-invoicing by handling the ‘extras’ too.

How Are e-Invoices Delivered via
? - 5 Corner Model

C2: The Supplier's Digital Mail Carrier

The supplier’s digital mail carrier sends it via the certified Peppol network in BIS3 format.

C4: Customer

The customer downloads the invoice into their accounting system.

C1: Supplier

The supplier creates an invoice in its system.

C3: Recipient's Digital Mailbox

The recipient’s digital mailbox receives the e-invoice from the network.

C5: Financial Administration

Selected data from invoices are shipped Financial Administration at purposes inspections VAT.

C1: Supplier

Your company creates an invoice in your system

C2: Supplier Access Point

Your digital mail carrier will receive the e-invoice and send it to the Peppola network in BIS3 format

Secure delivery via the Peppol network

C3: Customer Access Point

The recipient’s digital mailbox receives the e-invoice from the network

C4: Customer

The customer downloads the invoice into their accounting or invoicing software

C5: Financial Management

During the transfer at points C2 and C3, it receives selected data from invoices for VAT verification purposes

Safety is our top priority

Encryption

All communication is protected by end-to-end encryption (TLS/SSL), so your data is unreadable to third parties during transmission.

Identity Verification

PKI certificates verify the identities of network participants, ensuring that you are sending and receiving e-invoices from the correct partner.

Audit Trail

Every transaction is recorded—you can track the progress at any time and have proof of shipment and delivery.

Protection of Integrity

The documents are protected against unauthorized changes, so the content of the invoice remains unchanged and reliable throughout the entire transmission process.

Technical Components of a Digital Mailbox

1. Standard Format

Invoices comply with the European standard EN 16931, which ensures a uniform format throughout the EU. You can automatically generate the Peppol BIS3 (XML) format directly in Flowis.

2. Digital address

The unique Peppol ID generated by your digital mail provider serves as the address for delivering e-invoices.

Message Level Status confirms that your invoice has been successfully sent to the digital mail service and the Financial Administration.

Integration with the Financial Administration of the Slovak Republic ensures automatic reporting of data for VAT audits.

Secure encryption protects your business data.

Get ready for e-invoicing ahead of time

Voluntary participation will allow you to test everything in practice before January 1, 2027.

Would you like to try the Digital Mailman?

We’ll be launching the first version of the demo as early as spring 2026.

Meno *
Email *
Firma / Organizácia *
Koľko faktúr vystavujete mesačne? *
Koľko faktúr prijímate mesačne? *

We’ll get back to you with more information. If you have a specific question, you can ask it in the forum.