By March 31st, employers will receive a compliance notification (INPS, circular March 6, 2026, no. 6). INPS has set out methods for promoting compliance in contribution matters through the use of Synthetic Contribution Reliability Indices (ISAC). These indicators have been active since January 1, 2026, and were introduced to reinforce contribution correctness and prevent irregular work through the cross-referencing of fiscal and contributive data.
Furthermore, the inter-ministerial decree of February 27, 2026, approved the ISACs for the wholesale food trade sector and for the sector of hotel and non-hotel accommodation facilities. By March 31, 2026, INPS will send employers who are concerned a compliance letter indicating any deviations (minor or significant) from the normal values of the indicators connected to the reference ISAC model, estimating the working days that would bring the indicator back into the normal range. The communication is not an inspection and does not determine any irregularities; it is only meant for information and prevention.
The ISACs are derived from the integration of the Uniemens contributory data with the ISA fiscal data and the information resulting from application cooperation (UNISOMM). Employers receiving the compliance letter can provide feedback to INPS using the template attached to the circular. The template should be sent through the “Bidirectional Communication” function of the Taxpayer’s Social Security Drawer. If the employer believes it is necessary to regulate the contributory data, this can be done through the “Compliance regularization” section of the Uniemens flow, using the regularization Type “RE” and indicating the protocol and date of the letter. Any contributions due should be paid using form F24, reason RC01.
