Insurance Formal Complaint Letter Mexico (Carta de Reclamación a Compañía de Seguros)

An Insurance Formal Complaint Letter Mexico (Carta de Reclamación a Compañía de Seguros) is a written communication addressed to an insurance company (aseguradora) registered with the Comisión Nacional de Seguros y Fianzas (CNSF) formally demanding the payment of an insured claim, disputing a denial of coverage, or contesting an inadequate settlement offer. The document is governed principally by the Ley sobre el Contrato de Seguro (LCS), published in the Diario Oficial de la Federación on 31 August 1935 and substantially revised through subsequent amendments, which establishes the legal obligations of insurers toward policyholders (asegurados) and beneficiaries (beneficiarios) in Mexico.

Article 69 of the Ley sobre el Contrato de Seguro establishes the insurer's obligation to pay or deny a claim within thirty calendar days following the submission of the last required document by the insured. When the insurer fails to respond within this statutory period, or when it issues an unjustified denial, the policyholder acquires the right to formally demand compliance and to initiate proceedings before the Comisión Nacional para la Protección y Defensa de los Usuarios de Servicios Financieros (CONDUSEF), the federal consumer protection authority for financial services created by the Ley de Protección y Defensa al Usuario de Servicios Financieros (LPDUSF), published in the DOF on 18 January 1999.

The Carta de Reclamación a Compañía de Seguros serves as the foundational document in the claim dispute process. Mexican insurance law under Articles 8 through 10 of the Ley sobre el Contrato de Seguro requires that the insurance contract (póliza de seguro) be in writing and that all exclusions and conditions be stated in clear and precise terms — the standard de interpretación contra proferentem (Artículo 1857 of the Código Civil Federal) mandates that any ambiguity in insurance policy language be construed against the insurer who drafted the document.

The CONDUSEF operates a Registro de Contratos de Adhesión (RECA) where all insurance policy models sold in Mexico must be registered and approved, ensuring that pólizas de seguro comply with transparency standards established by CONDUSEF Circular CONSAR-CONDUSEF. When an insurer denies a claim based on policy exclusions not properly registered in RECA or not communicated to the insured at time of contracting, the denial is legally challengeable through the formal complaints process.

Insurance disputes in Mexico may also involve the Comisión Nacional de Seguros y Fianzas (CNSF), the sectoral regulator under the Secretaría de Hacienda y Crédito Público (SHCP), which oversees the solvency and conduct of insurers operating in Mexican territory under the Ley de Instituciones de Seguros y de Fianzas (LISF), published in the DOF on 4 April 2013 and in force since 4 April 2015. The CNSF has authority to impose sanctions on insurers who systematically deny or delay legitimate claims.

For auto insurance (seguro de automóvil), life insurance (seguro de vida), health insurance (seguro de gastos médicos mayores), home insurance (seguro de casa habitación), and commercial property insurance, the thirty-day payment period under Article 69 LCS runs from the moment the insured submits the complete claims file (expediente de siniestro) including all supporting documents required by the insurer. The formal complaint letter interrupts prescription periods and creates a written record that is essential for any subsequent CONDUSEF conciliation or judicial proceedings before the civil courts or arbitral tribunals having jurisdiction over insurance disputes.

The Mexican legal framework for insurance complaints distinguishes between reclamación extrajudicial (the formal demand letter stage), conciliación ante CONDUSEF (mandatory mediation through CONDUSEF's online and in-person platforms), and arbitraje o juicio ordinario mercantil (arbitration or commercial litigation before state or federal courts under the Código de Comercio and the Código Federal de Procedimientos Civiles). The Carta de Reclamación addresses the first stage and is a prerequisite for CONDUSEF proceedings.

An Insurance Formal Complaint Letter Mexico is needed whenever a policyholder, insured party, or beneficiary has submitted a valid claim to a Mexican insurer and the insurer has either failed to respond within the thirty-day statutory period under Article 69 of the Ley sobre el Contrato de Seguro, issued a denial that the claimant believes is unjustified or based on inapplicable exclusions, offered an inadequate settlement amount that does not reflect the actual indemnity owed under the policy terms, or requested excessive or unreasonable documentation beyond what the policy and applicable regulations require.

The document is needed when a vehicle owner files a claim under their seguro de automóvil (mandatory civil liability coverage or optional comprehensive coverage) following a traffic accident (siniestro vial) and the insurer delays or denies payment citing lack of documentation, pre-existing damage, or policy exclusions that were not clearly communicated at the time of contracting. Under the Ley de Instituciones de Seguros y de Fianzas (LISF) and CNSF Circular Única de Seguros y Fianzas (CUSF), insurers must investigate and resolve auto claims within defined timeframes and cannot impose requirements not stipulated in the registered policy.

The letter is required when the beneficiary of a life insurance policy (seguro de vida) is denied payment following the death of the insured, on grounds such as alleged non-disclosure of pre-existing conditions (enfermedades preexistentes) without the insurer having conducted a proper medical examination at policy inception, or citation of suicide exclusions without meeting the evidentiary burden required by Article 69-Bis LCS.

A formal complaint letter becomes necessary when a health insurance policyholder (seguro de gastos médicos mayores) receives a partial reimbursement or denial for hospitalization, surgery, or specialist treatment expenses covered under the policy, and the insurer's denial cites deductibles, coinsurance provisions, or network restrictions not properly disclosed in the póliza. Under CONDUSEF Circular 38/2016, health insurers must provide policyholders with a complete breakdown of any partial payment explaining the deductions applied.

The Carta de Reclamación is also needed as a precondition to filing a CONDUSEF conciliation request (Queja o Reclamación ante CONDUSEF) through the CONDUSEF portal or in person at any CONDUSEF regional office. CONDUSEF's conciliation service is free of charge for policyholders and can result in binding agreements enforceable as court judgments under Article 94 of the LPDUSF. Without a prior written formal demand to the insurer, CONDUSEF conciliation officers may request evidence that the policyholder attempted direct resolution before escalating the complaint.

A valid Insurance Formal Complaint Letter Mexico under the Ley sobre el Contrato de Seguro and CONDUSEF guidelines must contain the following essential elements to support claim enforcement or CONDUSEF proceedings.

Identification of the Claimant: Full legal name, RFC (Registro Federal de Contribuyentes), CURP (Clave Única de Registro de Población), official address, phone number, and email of the policyholder (asegurado/tomador del seguro) or beneficiary submitting the complaint. If the claimant is represented by an attorney (abogado) or authorized agent, a notarized power of attorney (poder notarial) under the Código Civil Federal must be attached.

Insurer Identification: Full corporate name and RFC of the insurance company, the specific branch, agency, or adjuster (ajustador) involved in the claim, and the physical or electronic address where the insurer is to receive formal communications.

Policy Details: The policy number (número de póliza), type of insurance (ramo de seguro), policy period (vigencia), sum insured or coverage limits (suma asegurada o límites de cobertura), and the date of loss or triggering event (fecha del siniestro). Reference to the specific policy clauses under which coverage is claimed and which the insurer has invoked as exclusions.

Claim History and Documentation: A chronological summary of the claim submission, including the date the siniestro was reported to the insurer, the claim number (número de siniestro or número de reporte), documents previously submitted, and any written or electronic communications received from the insurer's claims department (área de siniestros or área de reclamaciones). Copies of all supporting documents — repair estimates (presupuestos), medical bills (facturas médicas), death certificates (actas de defunción), police reports (actas del Ministerio Público or reporte de hechos viales from the Secretaría de Seguridad Ciudadana), and proof of loss (aviso de siniestro) — should be attached as numbered exhibits (anexos).

Legal Basis for Demand: Specific citation of Article 69 LCS establishing the thirty-day obligation, any applicable provisions of the Ley de Instituciones de Seguros y de Fianzas (LISF), relevant CNSF circulars, and Article 1857 of the Código Civil Federal (interpretation against the drafter) if the insurer is invoking ambiguous policy language. Reference to CONDUSEF's consumer protection mandate under the LPDUSF strengthens the demand.

Specific Relief Requested: The exact amount of indemnification demanded (monto reclamado) in Mexican pesos (MXN), the basis for that calculation, and any additional claims for default interest (intereses moratorios) under Article 135-Bis LCS for delays beyond the statutory payment period, as well as reimbursement of any expenses incurred as a direct result of the insurer's delay or denial.

Deadline and Escalation Notice: A clear deadline for the insurer to respond (typically ten to fifteen business days from receipt of the letter) and a statement that failure to comply will result in filing a CONDUSEF complaint and, if necessary, initiating judicial or arbitral proceedings before the competent civil or commercial court.

Forms-legal.com provides this Insurance Formal Complaint Letter Mexico template as a starting point for policyholders seeking to assert their rights under Mexican insurance law. Given the technical nature of insurance policy interpretation and the strict procedural requirements of CONDUSEF proceedings, review by a licensed abogado specializing in derecho de seguros or a CONDUSEF-authorized financial services defense attorney (Defensor del Usuario de Servicios Financieros) is strongly recommended for complex claims. The CONDUSEF also operates a free legal advisory service (Asesoría Jurídica) through its national network of regional offices.