28 September 2026

Americas Tax Roundup | 28 September 2026

 
 

A summary of the top weekly tax developments in the Americas

 
 
      
 

     This week's tax news from the Americas

  • Mexico proposes significant 2027 income tax and revenue measures
    On 8 September 2026, the Mexican President submitted to Congress the 2027 Economic Package, which would introduce new changes that would affect corporate taxes, such as limits on tax deductions and tax-loss utilization for most Mexican companies with 50 million Mexican pesos or more of annual taxable revenue for the relevant fiscal year. The proposals would also (1) reduce the threshold for net-interest deductions from 30% to 20% of adjusted tax earnings before interest, taxes, depreciation and amortization (tax EBITDA) and (2) change the timing of deductions and withholding for payments to foreign residents.
  • United States | Proposed regulations implement OBBBA's favorable expense apportionment changes to NCTI and FDDEI
    Treasury and the IRS proposed regulations that would implement expense apportionment changes made to net CFC tested income (NCTI) and foreign-derived deduction-eligible income (FDDEI) by the One Big Beautiful Bill Act. Under the proposed regulations, only a few deductions, such as certain foreign exchange and net operating losses, could be allocated and apportioned to foreign-source NCTI. Other deductions previously allocated and apportioned to foreign-source NCTI, such as interest or stewardship expenses, would instead be reallocated to US-source income, which would generally increase the limitation on foreign tax credits. The regulations would also exclude interest expense and research or experimental expenditures when determining deduction-eligible income and FDDEI, effectively allowing US taxpayers a larger deduction for that income.
  • Brazil incorporates OECD side-by-side agreement into its QDMTT rules
    In Normative Instruction (NI) No. 2,342/2026, dated 18 September 2026, the Federal Revenue Service incorporated two significant measures from the side-by-side agreement introduced by the OECD/G20 Inclusive Framework on BEPS into Brazil’s rules for Additional Social Contribution on Net Profit (the Brazilian QDMTT): (1) an extension of the transitional country-by-country reporting safe harbor to fiscal years beginning on or before 31 December 2027; and (2) the substance-based tax incentives safe harbor, referenced in Brazilian regulations as the GloBE simplification rule for substance-based tax incentives.
  
 
 

      This week's newsletters

  • Trade Lines – 18 September 2026
    Our trade newsletter for global business leaders delivers timely insights into the issues shaping global commerce—from tariff shifts and supply chain disruptions to legislative developments and compliance trends.
  • The Latest on BEPS and Beyond - 18 September 2026
    Our monthly report with brief summaries of the latest activity in the OECD Base Erosion and Profit Shifting (BEPS) project as well as country specific legislative and administrative activity, including global and regional policy trends related to the global focus on BEPS.
  
 
 

    Upcoming EY webcasts

A calendar of all upcoming EY webcasts is available.

  
 
 

    Recent EY podcasts

All episodes of the EY Cross-Border Taxation Spotlight and
EY Talks Tax are available through Apple podcasts.

  
 
 

   This week's EY Global Tax Alerts

     Americas

     Europe

     Middle East

  
 
 
 

Additional resources

EY Global Tax News Update
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EY Guides available for download
Browse our in-depth guides covering corporate tax, indirect tax, personal taxes, TP and other tax matters in more than 150 countries.

Comments. If you have any questions or suggestions about this newsletter, please email Tax News Update Help at: ustaxalertshelp@ey.com.

 
 
 
 

About Americas Tax Roundup

Published by NTD's Tax Technical Knowledge Services Group, Washington, D.C.
Jennifer Mannetta, writer and editor

Distributed weekly to all Americas Tax personnel.

 
 

Document ID: 2026-2054