Merchant's Credentials

⚠️ You are viewing documentation for API version 2026-02-03. The latest version is 2026-05-04. The new API version brings no changes to the Italian integration. However, it adds SIGN PT support, enabling teams planning to expand to Portugal to reuse the same integration already in place for Italy.

Revenue Agency’s merchants credentials

To access the Revenue Agency’s “Documento Commerciale Online” web procedure through the SIGN IT API lite, merchants must have personal Fisconline credentials. These credentials can be obtained by all taxpayers over the age of 16, including Italian citizens residing abroad, who possess an Italian VAT number.

SIGN IT API allows the input of Fisconline credentials through the fiscalization section of the createTaxpayer and the updateTaxpayer endpoints. The password, pin tax_id_number of the Fisconline user need to be provided for the specific Taxpayer (COMPANY or INDIVIDUAL). Please keep in mind that the end user will need an interface through which they can periodically update their credentials.

📘Note

The SIGN IT API supports authentication and submission of fiscal commercial documents to AdE’s web portal exclusively using Fisconline credentials. Other authentication methods, such as SPID, are not supported as they would require renewal every 24 hours.

Valid Fisconline credentials are only required in the LIVE environment. In the TEST environment, no validation is performed against AdE data, so placeholders can be used instead — such as the ones provided in our Postman collection.

⚠️Important

The Fisconline password expires every 90 days (we recommend renewing it every 60 days). Merchants are required to regularly update their credentials on the AdE portal and submit them via SIGN IT lite. Learn how in this article: SIGN IT - How to update the FISCONLINE credentials

Using credentials that are no longer valid will lead to service disruption, as the SIGN IT lite API will be unable to authenticate with the web procedure. For this reason, it is recommended to implement a periodic reminder for merchants (e.g. via email) to avoid issues such as the blocking of transaction data transmission.

How to request Fisconline credentials?

The natural person acting as a self-employed individual or as the legal representative of a business can request Fisconline credentials from the Revenue Agency. For a detailed Merchant Guide on how to request Fisconline credentials, please contact our sales team.

💡Tip

The taxpayer must manually do an initial log in to the Revenue Agency’s web portal in order to ensure that the credentials work properly and to accept the terms, conditions and additional clauses provided.

A new password must be set after the first login. The password provided by the Revenue Agency for initial access should not be used in the SIGN IT API.

Find more information through the FAQs of the Revenue Agency