Spain has notified the OECD that it has completed the internal procedures required for the Multilateral Instrument (MLI) to take effect for its tax treaty with Argentina, with the updated treaty provisions set to apply from 1 January 2027.
Spain has confirmed the completion of its internal procedures for the entry into effect of the Multilateral Convention to Implement Tax Treaty Related Measures to Prevent Base Erosion and Profit Shifting (MLI) in relation to its covered tax agreement with Argentina.
According to an update published by the Organisation for Economic Co-operation and Development (OECD), Spain deposited its notification on 26 May 2026, fulfilling a requirement stemming from a reservation it made under the MLI. Under that reservation, the MLI cannot become effective for a covered agreement until Spain deposits a notification confirming that its domestic procedures have been completed.
As a result of the notification, the MLI provisions will generally apply to the Spain–Argentina tax treaty from 1 January 2027 for taxes withheld at source. For all other taxes, the provisions will apply from 25 December 2026 in Spain. In Argentina, however, the MLI will apply to other taxes from 1 January 2027.
The notification forms part of Spain’s broader implementation of the MLI across its network of covered tax agreements. Spain has previously submitted notifications confirming the completion of internal procedures for numerous treaty partners, with effective dates ranging from June 2022 onwards.
The notification also reiterates Spain’s use of Article 35(1)(b) of the MLI to apply a shorter two-calendar-month period for the entry into effect of provisions under its tax treaty with Germany, instead of the standard six-month period. In addition, Spain reported the completion of procedures relating to amendments affecting its agreement with Finland, including the withdrawal of a reservation under Article 9(6)(a) and the entry into effect of additional notifications under Article 9(7) and 9(8).
Spain further confirmed that it has completed internal procedures for the application of the MLI’s arbitration provisions under Part VI with a number of jurisdictions, including Germany, Andorra, Australia, Austria, Belgium, Canada, France, Ireland and the UK.
The latest notification marks the final procedural step required for the MLI to take effect between Spain and Argentina under the terms of Spain’s reservation, bringing the treaty within the scope of the BEPS-related measures from the beginning of 2027.
