Mexico 2026: Practical Guide for Mining M&A and Project Finance, Tax, Customs & Cross‑border Risks

This Mexico 2026 mining M&A guide is a transactional playbook for buyers, sellers and lenders navigating the three reform pillars that now reshape every mining deal in the country: the 2026 Economic Package (tax reform), the sweeping Customs Law amendments and the SAT Tax Regularization Program. Mexico remains one of Latin America’s most active mining M&A jurisdictions, yet the regulatory ground has shifted significantly since late 2025. Deal teams that fail to update their due diligence scope, representations and warranties, and structuring assumptions risk material post‑closing exposure, from customs penalties and transfer‑pricing adjustments to unresolved SAT liabilities that survive signing.

Executive Summary, Immediate Tactical To‑Dos for Deals Closing in 2026

Before diving into the detail, every party to a mining transaction in Mexico should action the following items immediately:

• Expand tax due diligence scope. The 2026 tax reform Mexico measures impose tighter transfer‑pricing documentation, new informative returns to SAT and enhanced scrutiny of repatriation flows. Verify all open‑period filings before signing.
• Audit customs compliance from day one. The Customs Law amendments 2026 Mexico introduce mandatory Electronic Customs Valuation Declarations and strengthened documentary support obligations. Confirm that the target company, and its customs broker, meet every new requirement.
• Evaluate SAT tax regularization 2026 eligibility. Sellers with historic tax exposures should enrol before closing. Buyers must require proof of SAT clearance or negotiate a dedicated escrow.
• Update SPA reps and warranties. Add specific customs, AML and traceability representations. Standard tax indemnities drafted before 2026 no longer cover the new risk categories.
• Reassess holding‑company structures. Repatriation tax incentives Mexico 2026 create opportunities, but also documentation traps, for foreign holding entities receiving dividends from Mexican mining subsidiaries.
• Require lender‑side covenant updates. Project finance facilities should include compliance covenants tied to the reforms, with remediation rights and step‑in triggers for customs/tax breaches.
• Map AML and traceability obligations. New chain‑of‑custody requirements for mineral concentrates affect export declarations and beneficial‑owner reporting, confirm operational readiness pre‑close.
• Lock in advisory capacity early. Specialist Mexico‑focused mining counsel and experienced customs advisers are in high demand during 2026 deal season.

Quick Market Context and Deal Activity (2024–Q1 2026)

High commodity prices, particularly for silver, copper and lithium, have driven notable mining M&A activity in Mexico throughout 2024 and 2025, with transactions involving Gatos Silver, SilverCrest Metals and other mid‑cap producers signalling sustained buyer appetite. Global mining M&A reached nearly US$30 billion in the first three quarters of 2025, with Latin America capturing roughly 75% of deal value according to industry data. Mexico remained a primary destination within the region.

On the broader M&A front, 134 transactions closed in Mexico during 2025, amounting to US$16.5 billion, a 5% increase in deal volume over the prior year. White & Case data confirms a strong Q1 2026 start, with supply‑chain security and strategic capital deployment continuing to underpin deal activity across the mining sector. For acquirers evaluating cross‑border M&A Mexico opportunities, the commercial case remains compelling, but only if the 2026 regulatory changes are properly absorbed into deal structuring.

The 2026 Economic Package, Tax Reform Essentials for Mining M&A

Key Tax Changes Affecting M&A Transactions

The 2026 Economic Package, published in the Diario Oficial de la Federación (DOF) and elaborated by the Secretaría de Hacienda y Crédito Público (SHCP), introduces several measures with direct implications for mining deals. Industry observers expect these provisions to affect valuations, purchase‑price mechanics and post‑closing obligations across the sector:

• Transfer‑pricing documentation. Tightened rules require more granular contemporaneous documentation for intercompany transactions, including service fees, management charges and mineral off‑take agreements between related parties. Mining companies with complex international supply chains face the greatest compliance burden.
• Withholding tax adjustments. Updated withholding positions on payments to non‑residents, including royalties, technical‑service fees and interest, require treaty‑by‑treaty analysis. Buyers structuring acquisitions through foreign holding vehicles must verify that treaty relief still applies under the new rules.
• Repatriation incentives. The Economic Package includes temporary incentives designed to encourage the repatriation of profits held offshore. For mining holding structures, the likely practical effect will be a window of favourable tax treatment on dividend distributions from Mexican operating subsidiaries to qualifying foreign parents, provided prescribed documentation thresholds are met.
• Enhanced informative returns. Additional reporting obligations to SAT increase the volume and specificity of data that mining companies must file, creating new audit triggers and, by extension, new diligence scope items for acquirers.

SAT Tax Regularization 2026, Mechanics and M&A Relevance

The SAT Tax Regularization Program is a temporary incentive introduced for individuals and companies with income below specified thresholds to regularize historic tax exposures. According to practitioner summaries, the program allows eligible taxpayers to settle past‑due obligations under favourable terms, reduced penalties, streamlined filing and, in certain cases, partial forgiveness of surcharges.

For mining M&A, this program creates a narrow but powerful pre‑closing tool. Sellers with unresolved SAT notices or audit findings from open tax periods can use the program to cure those exposures before the deal closes, reducing the buyer’s indemnity risk and potentially unlocking higher purchase‑price certainty. Conversely, buyers must diligence whether the seller has used (or is eligible to use) the program, and must require contractual protections against exposures that fall outside its scope.

Sample SPA tax covenant language:

• “The Seller represents that it has filed all required tax returns with SAT for fiscal years [●] through [●] and that all tax liabilities shown thereon have been paid in full or are subject to a valid enrolment in the SAT Tax Regularization Program, evidence of which has been delivered to the Buyer.”
• “The Seller covenants to complete all steps required under the SAT Tax Regularization Program in respect of the Identified Tax Exposures prior to Closing and to deliver to the Buyer a SAT confirmation letter or equivalent evidence of regularization no later than [●] Business Days before the Closing Date.”
• “In the event that any Tax Exposure is not resolved or regularized by the Closing Date, an amount equal to [●]% of the estimated exposure shall be deposited into the Tax Escrow Account and held subject to the terms of the Escrow Agreement.”

Customs Law Amendments 2026, Import, Valuation, Traceability and AML Impacts

The Customs Law amendments 2026 Mexico represent the most significant overhaul of customs procedure in over a decade. According to the EY Economic Package briefing, the reform aims to improve, strengthen and modernise Mexican customs operations, with immediate consequences for mining companies that import heavy equipment, spare parts and chemical inputs.

Documentary and Electronic Valuation Changes

Under the amended Customs Law, importers must now support every customs entry with Electronic Customs Valuation Declarations backed by prescribed documentary evidence. The documentary support requirements have been expanded to include detailed commercial invoices, transport records, insurance certificates and, critically, evidence of the materiality of each transaction. KPMG’s summary of the General Foreign Trade Rules for 2026 highlights that companies and customs brokers face new obligations to ensure the “materiality” of foreign‑trade operations, a standard that goes beyond traditional paper compliance.

Traceability and AML Obligations for Minerals

Mining companies are particularly affected by the new traceability requirements. Chain‑of‑custody records for mineral concentrates, export declarations and beneficial‑owner disclosures must now meet heightened AML and traceability Mexico 2026 standards. Early indications suggest that enforcement will focus on high‑value mineral exports, silver, gold and copper concentrates, where the risk of undeclared value or origin misstatement is greatest.

Supply‑Chain Operators and Customs Brokers, Practical Steps

The reform reallocates certain compliance obligations between importers and their customs brokers. Deal teams should verify that existing customs brokerage contracts clearly assign responsibility for the new documentary valuation and electronic declaration requirements. The following table summarises the core documentary obligations by import type:

Due Diligence, Reps & Warranties and Pricing Mechanics After 2026 Reforms

The 2026 changes demand a fundamental expansion of M&A due diligence Mexico scope. Standard diligence protocols designed for pre‑reform conditions will miss critical exposure categories. The matrix below maps the key areas, items and recommended risk treatments:

Due Diligence Matrix for Mining M&A in Mexico (2026)

Tax Due Diligence, Red Flags Under the 2026 Reforms

Buyers should pay particular attention to: (i) open tax years where transfer‑pricing documentation does not meet the new contemporaneous‑documentation standard; (ii) any SAT invitations to regularize (cartas invitación) received but not acted upon by the seller; (iii) inconsistencies between informative returns and filed tax returns that may trigger automatic SAT review; and (iv) historical use of tax credits or incentives that may be subject to clawback under revised rules.

Customs and AML Due Diligence

Customs diligence must now extend to the full customs‑entry record for at least five years, verification of temporary‑importation permit compliance, and review of the target’s customs broker relationship, including whether the broker has been accredited under the new documentary valuation framework. AML diligence should cover beneficial‑owner records, suspicious‑activity reports, and compliance with the updated traceability rules for mineral concentrates.

Recommended Warranty Language and Indemnity Triggers

Buyers should insist on the following additions to SPA schedules:

• “The Company has complied in all material respects with all Customs Laws applicable to its importation and exportation activities, including the documentary valuation and traceability obligations introduced by the 2026 Customs Law amendments.”
• “The Seller shall indemnify the Buyer against any Loss arising from a customs assessment, penalty or sanction related to importation activities conducted prior to the Closing Date, including any failure to maintain Electronic Customs Valuation Declarations as required under the amended Customs Law.”
• “In the event that SAT initiates an audit of any pre‑Closing tax period within [●] months of Closing, the Buyer may draw upon the Escrow Amount to satisfy any resulting Tax Liability, surcharge or penalty.”

Structuring Cross‑Border M&A and Mining Project Finance in Mexico

Treaty Relief and Withholding Considerations

Mexico’s extensive double‑tax‑treaty network remains a key structuring tool for cross‑border M&A Mexico transactions. However, the 2026 Economic Package tightens the documentation requirements for claiming reduced withholding rates on interest, royalties and technical‑service fees. Acquirers using Netherlands, Luxembourg, Canada or other treaty jurisdictions must confirm that treaty powers of attorney, residency certificates and supporting documentation meet the new SAT standards, failure to comply can result in full statutory withholding on repatriated amounts.

Repatriation Incentives and Holding‑Company Structuring

The repatriation tax incentives Mexico 2026 offer a time‑limited opportunity to distribute accumulated profits from Mexican mining subsidiaries at reduced effective rates. Industry observers expect acquirers to integrate these incentives into their post‑closing cash‑management strategies, particularly where deal financing depends on upstream dividend flows. Holding‑company structures should be reviewed to ensure eligibility, and financing documents should include flexibility to take advantage of the incentive window.

Asset vs Share Sale, Tax and Compliance Comparison

Lender Security Packages

Mining project finance Mexico transactions require security packages that account for the 2026 reforms. Lenders should verify that pledges over mining concessions, share pledges over operating entities and assignment of receivables are structured to withstand regulatory changes. Intercreditor agreements should address priority of claims where customs or tax authorities assert statutory liens arising from post‑reform non‑compliance.

Using the SAT Tax Regularization Program in Transactions, A Practical Playbook

The SAT tax regularization 2026 program is best understood as a deal‑facilitation tool when used correctly. The following step‑by‑step approach is recommended:

1. Screen eligibility. Confirm the seller (or target entity) meets income thresholds and is not excluded by programme terms. Review SAT guidance for current eligibility criteria.
2. Identify exposures. Map all open‑period tax liabilities, unresolved SAT notices and audit findings that fall within the programme’s scope.
3. Enrol and file. Complete SAT enrolment, submit required documentation and make any initial payments within the programme’s filing window.
4. Negotiate deal protections. Inform the buyer; provide evidence of enrolment and expected timeline for SAT confirmation. Negotiate escrow for residual risk.
5. Close with confirmation. Deliver SAT confirmation letter (or equivalent evidence of regularization) as a condition precedent to closing, or fund escrow for unconfirmed exposures.

Worked example: A seller with a MXN 45 million transfer‑pricing adjustment from a 2022 SAT audit enrols in the regularization program, securing a reduction in surcharges. The seller delivers proof of enrolment and payment to the buyer at signing. The SPA provides for a dedicated escrow equal to 120% of the original assessment, released upon SAT confirmation of full regularization. If confirmation is not received within 12 months of closing, the buyer may draw on the escrow to satisfy any resulting liability.

Project Finance Implications, Lender DD, Covenants and Enforcement in Mexico 2026

Covenant Drafting for Post‑Closing Compliance

Facility agreements for mining project finance should include affirmative covenants requiring the borrower to: (i) maintain compliance with all 2026 Customs Law obligations, including documentary valuation and traceability requirements; (ii) file all SAT informative returns on time; (iii) notify the lender immediately of any customs assessment, SAT audit or AML investigation; and (iv) provide quarterly compliance certificates confirming adherence to the reformed regulatory framework.

Lender Remediation Rights on Tax and Customs Breaches

Lenders should negotiate the right to appoint independent customs and tax advisers to conduct compliance reviews at borrower cost upon the occurrence of a compliance event of default. Step‑in rights, allowing the lender to direct remediation steps where the borrower fails to act, should be included, particularly for customs violations that could result in seizure of imported equipment or suspension of export permits.

Insurance and Political/Regulatory Risk Mitigation

Political‑risk insurance and regulatory‑change coverage have become increasingly relevant for mining project finance Mexico transactions. Early indications suggest that underwriters are adjusting premium structures to reflect the 2026 reform landscape. Lenders should require borrowers to maintain comprehensive coverage, including customs‑penalty insurance where available, and should review policy exclusions for regulatory non‑compliance carefully.

Practical Checklists and SPA Drafting Snippets

The following checklists and drafting templates translate the diligence findings into contractual protections. They are designed to be adapted to specific transaction facts:

Pre‑Signing Checklist

• Obtain complete customs‑entry records for the past five years
• Verify IMMEX / temporary‑importation permit status and renewal dates
• Confirm SAT regularization enrolment and status (if applicable)
• Review customs broker accreditation under 2026 requirements
• Map all open SAT audit periods and outstanding notices
• Verify transfer‑pricing documentation meets 2026 contemporaneous standards
• Confirm chain‑of‑custody records for mineral concentrates
• Review beneficial‑owner registers and AML compliance files

SPA Drafting Snippets

• Customs compliance rep: “The Company has maintained all records, filings and declarations required under the Customs Law (Ley Aduanera), as amended by the 2026 reforms, in respect of all import and export transactions.”
• AML / traceability covenant: “From the date hereof until Closing, the Seller shall cause the Company to comply with all applicable AML and traceability requirements, including chain‑of‑custody obligations for mineral concentrates.”
• Tax escrow trigger: “If any SAT assessment, audit finding or penalty in excess of MXN [●] is issued in respect of any pre‑Closing tax period, the Buyer may instruct the Escrow Agent to release funds from the Tax Escrow Account in satisfaction thereof.”
• Customs indemnity: “The Seller shall indemnify and hold harmless the Buyer against any Loss arising from customs penalties, surcharges or seizures attributable to any failure of the Company to comply with Customs Law obligations prior to the Closing Date.”

Reporting Obligations by Entity Type After 2026 Reforms

Timeline and Key Dates for 2026 Reforms

Conclusion, Recommended Next Steps for Mining M&A and Project Finance in Mexico 2026

This Mexico 2026 mining M&A guide underscores three priorities for every deal closing this year. First, expand diligence scope to cover the full range of tax, customs, AML and traceability risks introduced by the 2026 reforms, standard pre‑reform checklists are no longer sufficient. Second, update every SPA, facility agreement and intercreditor arrangement with specific representations, covenants and indemnities tailored to the reformed regulatory framework. Third, engage specialist Mexico mining counsel and customs advisers early, the complexity and pace of regulatory change reward proactive structuring over reactive remediation. For broader context on cross‑border commercial transactions, consult the international commercial law guide or browse the Global Law Experts lawyer directory.

Sources

1. Diario Oficial de la Federación (DOF)
2. Servicio de Administración Tributaria (SAT)
3. Secretaría de Hacienda y Crédito Público (SHCP)
4. EY, Economic Package / Customs Law Brief
5. Trade.gov (U.S. ITA), Mexico Customs Law Reform
6. Chambers & Partners, Mining 2026 Mexico