Circular Letter No. 1426 — Introduce Adjustments to the Open Finance System Developer Portal

REF: Introduce adjustments to the Developer Portal 1 CIRCULAR LETTER NO. 1,426 October 5, 2026

To Information Provider Institutions, Account Provider Institutions, and other participants in the Open Finance System to whom it applies:

This Commission, within the framework of the implementation process of the Open Finance System, has deemed it necessary to incorporate new guidelines into the Developer Portal to facilitate the conduct of tests during the period prior to the entry into force of the corresponding obligations.

These guidelines contain operational guidance to support the conduct of tests in the Participants Directory and in the Sandbox environment, and describe their main functionalities, as well as the conditions and limitations applicable to such tests.

Therefore, by virtue of the legal powers granted by Article 5 of Law Decree No. 3,538 of 1980; the provisions applicable to the Open Finance System; and what is established in Exempt Resolution No. 10,010, of September 11, 2026, of this Commission, particularly regarding the power delegated to the General Director of Regulation to communicate adjustments, updates, and/or clarifications to the technical specifications of the regulations applicable to the Open Finance System, this Commission informs, through this Circular Letter, the incorporation into the Developer Portal of the following:

1. A new section is incorporated into the Developer Portal, named “Sandbox testing guides for the period prior to entry into force.”

The aforementioned guidelines are of an exclusively operational nature and are intended to support and facilitate the conduct of tests in the Participants Directory and in the Sandbox environment. Consequently, their incorporation does not alter or modify the current regulations, nor does it establish additional requirements or obligations for participants in the Open Finance System.

As a consequence of the foregoing, the Developer Portal administered by the Financial Market Commission is updated. The updated version is available on this Commission's website (www.cmfchile.cl).

The modification indicated will apply immediately.

Signed by: Francisco Cabezón F.
Position: General Director
Area: General Directorate of Regulation
Institution: Financial Market Commission
Date: 2026.10.05