Interests on Professional Fees Units: Active or Pure Rate?

1. Case background

On December 5, 2024, in the case "Cencosud S.A. c/ Garba S.A. and others," the court of first instance regulated fees in favor of the professionals who intervened in the case. The plaintiff’s attorney’s fees were regulated at 104 professional fees units (UMA), equivalent at that time to ARS 6,447,480.

At the end of September 2025, the attorney promoted the enforcement of his unpaid fees. When carrying out the liquidation, the attorney considered that 104 UMA amounted to ARS 7,882,056 (using the updated UMA value) and then calculated interest at the active rate of Banco de la Nacion Argentina. The attorney based the admissibility of said fee on the fact that it was the one used in the judgment on the merits of the case, based on Law 27423, article 54, which states, "Debts of fees, agreed or by final judicial regulation, when there is a default of the debtor, shall accrue interest from the date of the regulation of first instance and until the time of its effective payment,  which will be set by the judge of the case following the same criterion as that used to establish the updating of the economic values of the case."

In October 2025, the court of first instance rejected the liquidation and ordered the attorney to carry out a new one applying a pure interest rate of 6% per year without capitalization. To decide so, the Court considered that paying the attorney’s fees was an obligation of value and not an obligation to give money. As fees have been regulated in UMA, they are not crystallized at the time of default or subject to "the vicissitudes of depreciation that the passage of time may cause in their economic consistency." For this reason, since the payment of said fee must be made taking into account the updated value of UMA at the time of payment, applying the active rate to the principal credit—as the attorney did—would imply excessive interest.
 

2. House decision

The National Court of Appeals in Commercial Matters, Chamber F, confirmed the first instance ruling and rejected the claim to update the fees established in UMA to the active rate of the Banco Nacion. In its ruling, the Court emphasized the paradigm shift generated by Law 27423. In this sense, while in the previous regime the magistrates established fees as an obligation of money, under the new regime the payment of fees constitutes an obligation of value.

The Court pointed out that the difference between a value obligation and a money obligation cannot go unnoticed for the purpose of determining the interest rate applicable in the event of default. This is because depreciation over time affects the money obligation to a greater extent than the value obligation. The Court also emphasizes the fact that the default interest to be calculated on the fees by virtue of Law 27423, article 54 is not accrued from the date of the debtor's default, but from day the judge regulated the fees.

Consequently, the Court concluded that adding interest rates such as the Banco Nacion ones, which contains an inflationary component to a capital that is kept up to date (for the value of the UMA), entails a "disadvantageous mechanic that yields an objectively unfair result, regardless of the particularities and the economic reality involved." In turn, they indicated that, in such a circumstance, judges can use the tool provided for in articles 771 and 1091 of the Argentine Civil and Commercial Code and mitigate the interest that would result from applying Law 27423, article 54, and ordered the update to 12% per year, without capitalization. 
 

3. Conclusions

This case addresses a current and everyday issue in professional practice and reflects how national courts of the commercial jurisdiction mitigate the interests that would result from applying article 54 of Law 27423.

It is important to note that the different chambers of the commercial jurisdiction (except Chamber B, who applies the active rate of Banco de la Nacion Argentina) agree on applying a pure rate and not an active one when there is delay in the payment of fees regulated in UMA. The truth is that there is no unanimous criterion regarding which pure rate should be applied in these cases: while Chamber F and Chamber C[1] applied interest at 12% per year, not capitalized, Chamber A and E have opted for a fixed rate of 6% per year, not capitalized.[2]  However, Chamber D has applied a fixed rate of 8% per year, not capitalized.[3]