Ruling 191/2026 (interpello): biennial preventive composition for an associated professional, when the ISAs differ

In short: with ruling (risposta a interpello) no. 191, published on 23 October 2026, the Italian Revenue Agency clarifies that from the 2026-2027 biennium a professional who works on their own account and also takes part in a professional association can join the biennial preventive composition agreement (concordato preventivo biennale, CPB) alone, without the association joining, if the two activities fall under different ISAs. This applies as a result of the amendments made by Legislative Decree (d.lgs.) 148/2026 to the grounds for exclusion.

What does ruling 191/2026 say?

That the grounds for exclusion in letters b-quinquies) and b-sexies) of art. 11, paragraph 1, of Legislative Decree 13/2024 do not apply when the professional and the association carry out activities falling under different synthetic indicators of tax reliability (ISA). In that case, the professional accesses the CPB 2026-2027 "regardless of whether the Association joins".

The case: a notary who practises as a sole practitioner and is also an associate of a notaries' association active only in sales delegated by the enforcement judge (art. 591-bis of the Code of Civil Procedure). For 2024 the notary submitted ISA form DK01U (notarial offices, ATECO 69.10.20), and the association submitted form DK30U (support activities for legal, juridical and notarial activities, ATECO 69.10.30). The notary had already joined the CPB 2024-2025 and wished to renew.

What are the two grounds for exclusion at stake?

They were introduced by Legislative Decree 81/2025 (art. 9, paragraph 1, letter a) to prevent income from being shifted between a party that joins the composition and one that does not. In the text as amended by Legislative Decree 148/2026, as reported in the ruling:

• Letter b-quinquies): excluded is anyone who, in the previous tax period, individually declared self-employment income (art. 54, paragraph 1, of the TUIR, the Income Tax Code) and took part in a professional association (art. 5, paragraph 3, letter c, of the TUIR), in a professional partnership company or in a law firm company carrying out activities falling under the same ISA applied by the professional. The exclusion does not apply if the association or company joins the CPB for the same periods.
• Letter b-sexies): this is the mirror image. The association or company is excluded if not all partners or associates who individually declare self-employment income from activities falling under the same ISA applied by the entity join the CPB.

What has changed compared with before?

The reference to the "same ISA". In the formulation discussed in Revenue Agency circular 9/E of 24 June 2025, the exclusion affected the associated professional if the association did not join, unless the ISAs were not approved for the association's activity. With the amendments to art. 28, paragraph 1, letter b), numbers 1.2) and 1.3), of Legislative Decree 148 of 7 August 2026, the two exclusions do not apply if the professional and the entity fall under different ISAs.

According to art. 28, paragraph 3, of the same decree, cited in the ruling, the amendments apply "from the 2026-2027 biennium". For the 2024-2025 biennium the previous rules remain in force.

Access to the CPB for a professional who takes part in a professional association (from the 2026-2027 biennium)

Case	Professional	Association
Same ISA, the association joins	Can join	Can join if all associates with individual income under the same ISA join
Same ISA, the association does not join	Excluded (letter b-quinquies)	Does not join
Different ISAs	Can join even alone	Can join even if not all associates join

What are the limits of the opinion?

Three, and the Agency states them explicitly. The opinion concerns only the question asked: it does not assess the other requirements for access to the CPB, nor the other grounds for exclusion, forfeiture and termination. It presupposes that the ISAs and ATECO codes of the professional and the association are correctly applied, a check that remains with the tax administration. It holds as long as the professional and the association continue to carry out activities falling under different ISAs.

The articles of association of the association, on which the applicant had built its position (exclusive activity, impossibility of shifting income), is not the criterion the Agency uses to decide: the criterion is the ISA applied.

What to do in the office, client by client

• Map the associates: for each professional client who takes part in an association, a professional partnership company (STP) or a law firm company, compare the ISA form submitted for the previous period by the client and by the entity.
• Different ISAs: joining the CPB 2026-2027 is assessed for the individual, without coordinating with the other associates.
• Same ISA: joining must be decided together. If the entity does not join, the associate is excluded; if not all associates with individual income join, the entity is excluded.
• Document in the client file the check carried out and the ISA forms compared.

A new tax advisory engagement, or the preparation of a ruling such as this one, also goes through the client's anti-money laundering customer due diligence. With the free customer due diligence checklist based on the CNDCEC Technical Rules method you calculate the risk and the measure due for the service and print the record to be kept.

Sources

• Agenzia delle Entrate (Italian Revenue Agency), ruling (risposta a interpello) no. 191/2026 (biennial preventive composition, professional association, different ISAs), published on 23/10/2026, accessed 23/10/2026
• Legislative Decree (D.lgs.) of 12 February 2024, no. 13, art. 11, paragraph 1, letters b-quinquies) and b-sexies), on Normattiva
• Legislative Decree (D.lgs.) 7 August 2026, no. 148, art. 28, paragraph 1, letter b), numbers 1.2) and 1.3), and paragraph 3, as cited in ruling 191/2026
• Agenzia delle Entrate, circular no. 9/E of 24 June 2025, as cited in ruling 191/2026