US Expats in Mexico: ISR Rates, Treaty Gaps & the Fideicomiso (2026)

Mexico hosts the largest US citizen population of any country — approximately 1.5 million Americans live there, drawn by proximity, climate, cost of living, and a growing remote-work culture. It is also one of the most underestimated tax jurisdictions for Americans abroad. Mexico's ISR (Impuesto Sobre la Renta) is a genuinely progressive system with rates reaching 35% — high enough that the Foreign Tax Credit typically eliminates any residual US federal tax for professional earners, placing Mexico in the same high-tax category as Germany, the UK, and Australia. But Mexico adds several traps not found in those countries: coastal and border-zone property requiring a fideicomiso bank trust with FBAR implications, mandatory AFORE pension accounts that are likely PFICs under US tax law, and — uniquely among major US-expat destinations — no functioning Social Security totalization agreement despite a signed 2004 treaty that was never ratified.

1. Mexico Income Tax (ISR) at a Glance

Mexico taxes resident individuals under the Impuesto Sobre la Renta (ISR) at progressive rates on annual net income. Residents pay ISR on worldwide income; non-residents pay ISR only on Mexican-source income at flat withholding rates (25–30% on gross proceeds). The 2026 annual ISR brackets for resident individuals are:¹

USD equivalents are illustrative at 20:1 MXN/USD. The peso has historically ranged from 17 to 22+ per dollar; your actual USD exposure depends on prevailing rates at the time of income receipt. ISR is calculated on annual net taxable income after authorized personal deductions (IMSS contributions, certain medical expenses, tuition, mortgage interest on one principal residence). Mexico has no broad standard deduction equivalent, but personal deductions can meaningfully reduce the effective rate for some filers.

For a US professional earning MXN 2,000,000/year (~$100,000 USD at 20:1), the 34% marginal rate applies on income above MXN 1,503,903. The effective ISR rate on MXN 2,000,000 is approximately 28–30%. Compare this to the US federal effective rate for a single filer at $100,000 income (roughly 18–22% after the standard deduction): Mexico's effective rate exceeds the US rate at this income level, meaning the FTC can fully offset the US liability with credit to spare.

2. FEIE vs Foreign Tax Credit: Why FTC Usually Wins in Mexico

US citizens living abroad use two primary mechanisms to reduce double taxation on foreign earned income:

• Foreign Earned Income Exclusion (FEIE, Form 2555) — excludes up to $132,900 of foreign earned income from US gross income in 2026.²
• Foreign Tax Credit (FTC, Form 1116) — credits Mexican ISR paid dollar-for-dollar against your US tax liability on the same income, subject to the IRC §904 limitation.³

Why FTC typically wins in Mexico: Mexico's ISR rates equal or exceed US federal rates for most professional income levels. A US attorney earning $150,000 USD in Mexico City pays approximately $45,000 in Mexican ISR (effective rate ~30%). The US federal tax on that income (single filer, standard deduction) is roughly $35,000. The FTC credits the full $35,000 US liability — leaving $0 owed to the IRS — while the remaining $10,000 of unused FTC generates a 10-year carryforward under IRC §904(c).

Concrete example — FEIE vs FTC at $150,000 income:

• With FTC: US tax before FTC ~$35,000 → FTC credit $35,000 → residual US tax $0. Mexico ISR: ~$45,000. Total: $45,000.
• With FEIE: FEIE excludes $132,900. Remaining US-taxable income: $17,100. US tax on $17,100: ~$1,800. Mexico ISR (unchanged): ~$45,000. Total: $46,800.
• FTC saves $1,800 in this scenario — and preserves IRA contribution eligibility (see below).

When FEIE might still be appropriate in Mexico:

• Lower earners (<$50,000 USD): At this income level, the FTC carryforward benefit is modest and FEIE's simplicity is attractive. Both methods typically result in $0 US federal tax, since Mexico taxes even low earners at effective rates exceeding US rates.
• Roth conversion strategy: FEIE clears earned income from the US return, potentially opening low-bracket headroom for Roth IRA conversions. (Roth conversions are ordinary income, not earned income — FEIE doesn't exclude them.)
• Simplicity preference: FEIE doesn't require tracking §904 income baskets, the FTC limitation formula, or carryforward accounts.

Traps that apply regardless of FEIE vs FTC choice:

• IRA eligibility: FEIE reduces "earned income" for IRA/Roth IRA contribution purposes under IRC §219(f)(1). If FEIE excludes your entire earned income, you have $0 basis for retirement account contributions that year. FTC preserves earned income and IRA eligibility — a significant long-term advantage. See our FEIE guide for the full analysis.
• Self-employment tax: Neither FEIE nor FTC reduces the 15.3% SECA (self-employment) tax owed to the US. And unlike Germany, UK, or Canada, there is no functioning US-Mexico totalization agreement to reduce or eliminate it. Self-employed US citizens in Mexico owe full SECA to the US. See Section 6 below.
• Net Investment Income Tax (NIIT): The 3.8% NIIT under IRC §1411 applies to US taxpayers above $200,000 (single) / $250,000 (MFJ) in MAGI. Mexican taxes on investment income may not be fully creditable against NIIT depending on basket allocation — creating residual NIIT exposure even when earned income is fully sheltered.
• 5-year FEIE revocation lock-in: Once you elect FEIE, revoking it requires an IRS application and you cannot re-elect FEIE for 5 years without IRS consent. Don't elect FEIE casually if circumstances may change. Use our FEIE vs FTC calculator to model your specific numbers.

3. Mexican Tax Residency and RFC Registration

Mexico's tax residency trigger is a bright-line rule: presence in Mexico for more than 183 calendar days in any 12-month period establishes Mexican tax residency under Article 9 of the Ley del Impuesto sobre la Renta (LISR).⁴ Once you are a Mexican tax resident:

• Mexico taxes you on worldwide income, not just Mexican-source income
• You must register with SAT (Servicio de Administración Tributaria — Mexico's tax authority) and obtain an RFC (Registro Federal de Contribuyentes) tax identification number
• You must file an annual ISR declaration (declaración anual) by April 30 of the following calendar year
• You must report foreign financial accounts to Mexico's UIF (Unidad de Inteligencia Financiera) under Mexico's domestic financial reporting rules

The digital nomad trap. Remote workers living in Mexico — employed by US companies, paid in USD — often assume they owe no Mexican tax because their employer and income source are in the United States. This is incorrect. Mexico taxes worldwide income of its residents regardless of where the employer or payment is located. A software engineer employed by a San Francisco company, working from Oaxaca for 200 days per year, owes Mexican ISR on their full salary once the 183-day threshold is crossed.

Visa type doesn't change the 183-day clock. The popular Residente Temporal and Residente Permanente visas imply intent to live in Mexico. Physical presence counts toward the 183-day threshold regardless of visa type. The 183 days do not need to be consecutive — cumulative days within a 12-month period count.

Treaty tiebreaker for dual residents. Article 4 of the US-Mexico tax treaty provides a tiebreaker for persons who would be residents of both countries under their respective domestic laws. The tiebreaker applies the closer-connection test in order: permanent home, center of vital interests, habitual abode, then nationality. A US citizen with a primary home in Mexico City and an apartment in Los Angeles is likely a Mexican treaty resident if Mexico is their primary residence. However — the saving clause (Article 1(3)) means the United States retains the right to tax its citizens on worldwide income regardless of the treaty tiebreaker outcome. The tiebreaker mainly affects which country has "first bite" and which provides FTC relief against the other's tax.

4. Mexican Real Estate: The Fideicomiso

US citizens can own real estate anywhere in Mexico. Outside the restricted zone, Americans can hold direct title (escritura) in their own name, the same as any Mexican citizen. Inside the restricted zone — defined under Article 27 of the Mexican Constitution as land within 50 km of any coastline and 100 km of any international border⁵ — foreigners must use a fideicomiso (bank trust) or a Mexican corporation for residential property.

How the fideicomiso works: A licensed Mexican bank acts as trustee and holds legal title to the property. You are the trust beneficiary — with full rights to use, rent, sell, improve, and designate heirs. The trust term is 50 years, renewable indefinitely at nominal cost. Annual fees to the bank trustee typically range from $500–$1,500+ USD depending on the bank, property value, and location. Setup costs (notary fees, permit fees, bank establishment fee) typically add 4–7% to the property purchase price in the restricted zone.

US tax treatment of fideicomiso property: The IRS has historically treated US citizens holding Mexican real estate via fideicomiso as the direct beneficial owners of the underlying property — not as holders of a "foreign grantor trust" requiring Form 3520 annual disclosure — provided the trust holds only personal-use residential real estate and the beneficiary holds all effective ownership rights.⁶ This interpretation is not codified in a general IRS revenue procedure; it derives from the specific economics of the arrangement. If your fideicomiso has non-standard provisions (e.g., multiple beneficiaries, rental income flowing through the trust, or trust assets beyond the real estate itself), get qualified tax counsel before assuming Form 3520 is not required.

IRC §121 primary residence exclusion: The $250,000 (single) / $500,000 (MFJ) capital gains exclusion under IRC §121 can apply to a Mexican property's gain on sale, subject to the standard 2-of-5-year ownership and use test. Two significant complications:

• Currency gain component: The IRS measures gain in USD, not pesos. If you purchased for MXN 5,000,000 when the rate was 18:1 ($277,778 USD cost basis) and sell for MXN 6,000,000 when the rate is 22:1 ($272,727 USD proceeds), you have a USD loss despite a MXN 1,000,000 nominal gain in local currency. Conversely, if the peso strengthens, your USD-measured gain can substantially exceed the local-currency appreciation. Currency movements create or destroy taxable gain independently of local real estate prices.
• Mexican capital gains tax: Mexico imposes ISR on real estate gains. Mexican tax residents pay ISR on net gain at progressive ordinary income rates; non-residents pay a flat 25% withholding on gross proceeds or 35% of net gain at their election. The Mexican CGT paid can be used as an FTC credit in the passive income basket against US capital gains tax on the same property — reducing or eliminating the US exposure. The Mexican notario público typically withholds ISR at closing.

FBAR for the fideicomiso: The fideicomiso is a foreign financial account. The underlying asset (the property) should be reported on FBAR (FinCEN 114) if the aggregate value of all foreign accounts exceeds $10,000. Most restricted-zone properties are worth well over $10,000 — FBAR reporting is essentially always required. File annually via the FinCEN BSA E-Filing system by October 15.

5. AFORE: The Mandatory Mexican Pension PFIC Trap

Employees in Mexico's formal sector are automatically enrolled in AFORE (Administradora de Fondos para el Retiro), Mexico's privately managed pension system created by the 1997 IMSS reform. Contributions are split among the employee (~1.125% of salary), employer (~5.15%), and the federal government (~0.225%), directed into individual accounts managed by licensed AFORE administrators (Citibanamex AFORE, Profuturo, Principal, XXI Banorte, and others).⁷

Why AFORE creates US tax problems for US citizens:

1. PFIC classification. The investment funds inside AFORE accounts are typically Mexican-domiciled mutual funds that qualify as Passive Foreign Investment Companies (PFICs) under IRC §1297 — meeting either the income test (75%+ of gross income from passive sources) or the asset test (50%+ passive assets). Unlike the Canadian RRSP (which benefits from a specific treaty election under Rev. Proc. 2014-55) or the UK SIPP (treated as an employer pension plan under Article 18 of the US-UK treaty), there is no IRS guidance or US-Mexico treaty provision granting favorable US tax deferral to AFORE accounts. Without a timely QEF or mark-to-market election, gains inside an AFORE face the §1291 excess distribution regime — taxed at the top 37% ordinary income rate plus a compounding interest charge under §6621 going back to when each year's gain accrued. Our PFIC calculator illustrates how quickly the interest penalty compounds on untreated PFIC gains.
2. Employer contributions are likely US-taxable compensation. Your employer's AFORE contribution (~5.15% of salary) is likely US-taxable to you as additional wages in the year contributed — because there is no US statutory deferral mechanism or treaty provision covering AFORE employer contributions the way §401(k) elections or RRSP treaty positions work. The result: you pay US income tax on the employer's contribution as additional compensation, then face PFIC taxation on the growth inside the account.
3. FBAR reporting. AFORE accounts are foreign financial accounts — include them in your FBAR aggregate if total foreign accounts exceed $10,000.
4. Form 8938 (FATCA). AFORE is a "specified foreign financial asset" for Form 8938 purposes. Report if aggregate foreign financial assets exceed $300,000 (single) / $600,000 (MFJ) at any point in the year, or $200,000 / $400,000 at year-end.
5. Form 8621 per PFIC position. If you make a QEF or mark-to-market election (or the §1291 default applies), file Form 8621 for each PFIC position held in the AFORE each year.

What to do: A US citizen entering Mexican formal employment should consult an expat tax specialist before their first AFORE contributions accumulate. A timely QEF election (if the AFORE administrator provides the required annual income statements) or mark-to-market election can avoid the §1291 interest penalty regime. Self-employed US citizens working on an autonomous (independent contractor) basis in Mexico do not participate in AFORE or IMSS, avoiding this trap entirely.

6. No Functioning Totalization Agreement with the United States

The United States has Social Security totalization agreements with 30 countries — including Germany, the UK, Canada, Australia, Japan, and South Korea — that eliminate dual social security contributions and allow workers to combine benefit credits from both countries. Mexico is not on this list.⁸

A US-Mexico totalization agreement was signed in Guadalajara on June 29, 2004. Under 42 USC §433, executive-branch totalization agreements must be submitted to Congress for a 60-day review period before entry into force. The 2004 Mexico agreement was never transmitted to Congress and has never been implemented.⁹ It remains legally unenforceable as of 2026.

Practical consequences for US citizens in Mexico:

• Self-employed US citizens owe full 15.3% SECA (self-employment) tax on net self-employment income regardless of any Mexican IMSS contributions. There is no Certificate of Coverage mechanism to exempt you from one country's system. A freelance consultant in Mexico City earning $120,000 net owes $18,360 in SECA to the US plus any applicable Mexican IMSS contributions — with no offset.
• US employees working for US employers in Mexico typically remain subject to US FICA (Social Security + Medicare payroll taxes). If the employer has a taxable presence (permanent establishment) in Mexico, IMSS contributions may also apply, creating dual social insurance obligations.
• Mexican IMSS contribution years don't count toward US Social Security. Years of IMSS contribution in Mexico don't build US Social Security credits, and US Social Security credits don't reduce Mexican pension eligibility calculations. You may accumulate two partial records that don't combine — potentially qualifying for neither country's full pension without meeting each country's independent thresholds.

Compare: a US citizen working in Germany or Canada can obtain a Certificate of Coverage from the SSA that formally exempts them from the host country's social insurance system for the covered period. No equivalent mechanism exists for Mexico, and no prospect of imminent change is publicly anticipated.

7. FBAR and FATCA for Mexican Financial Accounts

All Mexican financial accounts must be evaluated for US reporting under FBAR and FATCA:

• FBAR (FinCEN 114): Required if the aggregate maximum value of all foreign financial accounts exceeds $10,000 at any point during the calendar year. Reportable accounts include Mexican bank accounts (Banamex/Citibanamex, BBVA México, Santander México, Banorte, HSBC México, Scotiabank México, etc.), brokerage accounts at Casas de Bolsa, AFORE accounts, investment accounts, and any fideicomiso where you are a named beneficiary. Annual deadline: April 15 (automatic extension to October 15 — no form required). Filed free via FinCEN's BSA E-Filing system.
• Form 8938 (FATCA): Required for US citizens abroad if total specified foreign financial assets exceed $300,000 (single) / $600,000 (MFJ) at any point during the year, or $200,000 / $400,000 at year-end. Thresholds for US residents are lower ($50,000/$100,000). Mexican accounts subject to Form 8938 include the same accounts as FBAR plus fideicomiso-held real estate if the fideicomiso is treated as a foreign financial account.
• FATCA compliance environment in Mexico. Mexico is a FATCA IGA Model 1 partner — Mexican financial institutions report US-person account data to SAT, which transmits it to the IRS annually. This makes the IRS more likely to have visibility into your Mexican accounts than you might expect. Proactive, correct FBAR and Form 8938 reporting is essential.
• Penalty exposure. FBAR civil non-willful penalty: $16,536 per filing violation per year (2026 inflation-adjusted); willful: the greater of $165,353 or 50% of account balance. The Supreme Court's Bittner (2023) decision held that non-willful penalties apply per report (not per account), which reduced exposure for some filers — but the risk of substantial penalties for non-reporting remains. See our FBAR/FATCA guide for the full penalty framework and streamlined filing procedures for catching up on missed years.

8. The US-Mexico Tax Treaty

The United States-Mexico Income Tax Convention was signed September 18, 1992 and entered into force January 1, 1994. A protocol was signed November 26, 2002 and entered into force July 3, 2003.¹⁰

The saving clause (Article 1(3)). Like all US income tax treaties, the US-Mexico treaty preserves the United States' right to tax its citizens as if the treaty had never been signed. For US citizens living in Mexico, most treaty benefits do not reduce US tax on Mexican earned income. The treaty does not exempt your Mexican salary from US taxation, reduce US capital gains tax on Mexican-source gains, or create a deduction for Mexican pension contributions.

Saving clause exceptions that do help US citizens:

• Social security / pension provisions (Article 18): Pensions paid under Mexico's IMSS social security law may generally be taxed only in Mexico for non-US-citizen recipients. For US citizens receiving IMSS pensions, the US retains the right to tax under the saving clause — but FTC on the Mexican-source pension income can offset the US tax.
• Government pay (Article 19): Remuneration paid by the Mexican government to Mexican-citizen employees is typically only taxable in Mexico. Limited applicability for most US expats.
• Tiebreaker (Article 4): As discussed in Section 3, useful for establishing primary treaty residency in dual-residency situations — mainly relevant for cross-border commuters (e.g., Tijuana/San Diego, Juárez/El Paso) and tax-reporting planning.

No treaty help on AFORE or PE risk. Unlike the US-UK treaty (which covers SIPP contributions under Article 18) or the US-Canada treaty (Rev. Proc. 2014-55 for RRSP/RRIF), the US-Mexico treaty has no provision granting favorable US tax treatment to AFORE contributions. Employers of US citizens in Mexico should also be aware that a permanent establishment created by the employee's presence in Mexico may create Mexican corporate tax obligations for the US employer — a topic outside individual income tax planning but relevant for remote-worker structuring.

9. State Tax Residency: The Domicile Trap in Mexico

Moving to Mexico does not automatically end your US state tax obligations. California, New York, Virginia, and several other states assert continued residency for years after departure if you retain state ties — a home, a professional license, a vehicle registration, a dependent in the state. California does not recognize the federal Foreign Earned Income Exclusion: a California tax resident in Mexico owes California income tax on worldwide income with no FEIE offset. See our state residency guide for the full domicile-severance checklist.

The border-state complexity. US citizens who split time between a border state and Mexico (Arizona/Sonora, California/Baja, Texas/Coahuila-Tamaulipas, New Mexico/Chihuahua) face the most complex analysis. Maintaining a permanent place of abode in California or New York while working in Mexico — even if spending the majority of days in Mexico — may preserve state residency obligations. Physical presence counts differently for each state's resident vs. domiciliary analysis.

10. What to Do Before Moving to Mexico

1. Model FEIE vs FTC for your income and filing status. Mexico's high ISR rates usually favor FTC for earners above ~$80,000 USD. Run the numbers with your projected income, filing status, and any capital income. Use our FEIE vs FTC calculator as a starting point, then confirm the decision with a Mexico-specialist expat advisor before your first year.
2. Plan your AFORE strategy before starting Mexican formal employment. Enrollment in AFORE is automatic for IMSS-covered employees. Get specialist guidance on PFIC election timing — a timely QEF or mark-to-market election, filed on the tax return for the year you first hold the PFIC, is far easier than cleaning up years of untreated §1291 accumulations.
3. Check whether your planned property is in the restricted zone. Properties within 50 km of any coast or 100 km of any land border require a fideicomiso. Build the annual trustee fee and setup costs into your budget, and understand the ongoing FBAR reporting obligation before you close.
4. Sever your prior US state domicile before departure. Change driver's license, voter registration, professional licenses, and banking relationships to a no-income-tax state (Texas, Florida, Nevada) or document your Mexico domicile clearly. Don't leave a California or New York apartment "just in case" — it anchors state residency.
5. Register for RFC and understand the 183-day clock. Once you plan to exceed 183 days in Mexico, proactively register with SAT rather than waiting for year-end. Late registration and unfiled declaraciones annuales attract penalties under Mexican law in addition to US compliance issues.
6. Quantify the SECA exposure if self-employed. Full 15.3% SECA on net self-employment income, with no totalization relief, can be a $15,000–$25,000+ annual obligation for a US professional earning $100,000–$150,000. Build this into your cost structure before leaving a W-2 job.
7. Set up FBAR tracking from Day 1. Create a tracking system for all Mexican financial accounts from the moment you open them. The $10,000 FBAR aggregate threshold can be reached on day one of opening a Mexican bank account sufficient for rental deposits and living expenses on a professional salary.
8. Plan any Roth conversions before departure. The year you leave a US employer may be a low-income year — a window for Roth conversions at reduced rates before Mexican-year income begins. Once in Mexico on FTC, Roth conversions generate US ordinary income competing for FTC basket capacity.

What a Mexico-Specialist Expat Advisor Handles

A US generalist financial advisor will often decline non-resident clients and won't know the AFORE PFIC issue. A Mexican financial advisor (contador) will optimize AFORE contributions and may recommend Mexico-domiciled investment funds — both of which can create severe US tax complications. A US-licensed, fee-only advisor who focuses on US citizens in Mexico handles:

• FEIE vs FTC decision modeling — income level, filing status, housing exclusion, self-employment status
• AFORE PFIC analysis — QEF vs mark-to-market election, employer contribution US-taxability, Form 8621 filings
• Fideicomiso beneficial ownership analysis and FBAR / Form 8938 / Form 3520 reporting assessment
• Real estate gain planning — §121 exclusion, currency gain calculation, Mexican CGT as FTC credit
• Self-employment tax planning — SECA exposure without totalization, entity structure analysis (US LLC vs Mexican S.A.S.)
• FBAR, Form 8938, Form 8621 preparation and coordination with a Mexican contador for the declaración anual
• State domicile severance documentation — California, New York, and other aggressive states
• Non-US spouse planning for mixed Mexican-American couples: QDOT trust (if estate approaches $15M), non-citizen spouse annual gift limit ($194,000 in 2026)¹¹
• Exit tax planning under IRC §877A for US citizens considering renouncing citizenship

1. SAT (Servicio de Administración Tributaria): 2026 ISR annual income tax brackets for resident individuals — progressive rates 1.92%–35%; 30% marginal rate applies on income above MXN 590,795/year. USD equivalents at 20:1 MXN/USD are illustrative. Cross-referenced with PwC Mexico Tax Summaries 2026: taxsummaries.pwc.com/mexico/individual/taxes-on-personal-income. Official SAT rate tables: sat.gob.mx
2. IRS Publication 54, Tax Guide for U.S. Citizens and Resident Aliens Abroad — Foreign Earned Income Exclusion. 2026 FEIE limit $132,900 per IRS Rev. Proc. 2025-67. irs.gov/publications/p54
3. IRC §901–§905; IRS Form 1116 Instructions (2026). Foreign Tax Credit framework — §904 limitation, general vs. passive income baskets, 1-year carryback / 10-year carryforward under §904(c). irs.gov/forms-pubs/about-form-1116
4. Ley del Impuesto sobre la Renta (LISR), Artículo 9: establishes 183-day presence test for tax residency; residents subject to ISR on worldwide income. Full LISR text: diputados.gob.mx/LeyesBiblio/pdf/LISR.pdf
5. Mexican Constitution, Article 27; Ley de Inversión Extranjera (LIE). Restricted zone defined as 100 km from international borders and 50 km from any coastline. Foreigners must use fideicomiso or Mexican company for restricted-zone residential real estate. LIE text: diputados.gob.mx/LeyesBiblio/pdf/116.pdf
6. IRS guidance on fideicomiso US tax classification. The IRS has historically treated fideicomiso beneficiaries as beneficial owners of the underlying real estate for US income and estate tax purposes where the trust is a conveyancing mechanism and the beneficiary holds all substantive ownership rights. No binding revenue procedure exists — analysis depends on specific trust terms. See IRS FAQ on foreign grantor trusts and Form 3520 instructions: irs.gov/forms-pubs/about-form-3520
7. CONSAR (Comisión Nacional del Sistema de Ahorro para el Retiro): employer AFORE contribution 5.150% of integrated daily wage; employee contribution 1.125%; government contribution 0.225%. Individual AFORE account enrollment mandatory for IMSS-affiliated employees. gob.mx/consar. IRC §1297 (PFIC definition) and IRS Form 8621 instructions govern PFIC election procedures: irs.gov/forms-pubs/about-form-8621
8. SSA: U.S. International Social Security Agreements — list of countries with active totalization agreements as of 2026. Mexico does not appear on the SSA's list of 30 countries with active agreements. ssa.gov/international/agreements_overview.html
9. SSA: U.S.-Mexican Social Security Agreement — text and status. Agreement signed Guadalajara, June 29, 2004; not entered into force as of 2026 due to failure to submit for Congressional review under 42 USC §433. ssa.gov/international/Agreement_Texts/mexico.html; GAO-03-993 background: gao.gov/products/gao-03-993
10. IRS: United States-Mexico Income Tax Convention, signed September 18, 1992, entered into force January 1, 1994. Protocol signed November 26, 2002, entered into force July 3, 2003. Full text: irs.gov/pub/irs-trty/mexico.pdf
11. IRC §2523(i): Annual exclusion for gifts to non-citizen spouses. 2026 limit $194,000 per IRS Rev. Proc. 2025-67. Non-citizen spouses do not qualify for the unlimited marital deduction under IRC §2056(d). See also non-US spouse planning guide.

US tax values verified as of May 2026 against IRS.gov, SSA.gov, and SAT (sat.gob.mx). ISR brackets reflect 2026 rates per SAT and PwC Mexico Tax Summaries. USD equivalents are illustrative at 20:1 MXN/USD — the peso/dollar rate fluctuates; actual USD exposure depends on prevailing rates at time of income or transaction.