About us
MGCS
It is an accounting-financial services firm that works every day to achieve international leadership, founded in 1994 by Oscar Garcia and Serge Massat, is composed of Mexican and French accountants.
- Fully committed to our clients and employees, we carry out our operations through our central values: Compromise, honesty, adaptability, and respect.
- As a result of our multicultural team and continuous updating, our main clients are foreign companies that establish legal entities in Mexico. We advise them with the necessary processes for them to comply with their obligations before the Law.
- Several years of experience in the field have helped us identify our clients’ main needs and adapt to them, always aiming to facilitate the decision-making process and the best business development.
- A qualified and specialized team advises each of our clients on the different MGCS areas of expertise.
- + In a globalized world, MGCS acts always looking for the resource’s efficiency, playing its part: Think globally, act locally.

For every issue, there is a time and specific opportunity.
Partnerships
Contact us
Audit
- Financial Statement´s Audit
- Study and evaluation of Intern Control
- Tax opinion
Back office
Bank account procedures in different Mexico’s banks, making payments to suppliers by request of the client, payroll payment, social charges, taxes, investments, sending of bank account statements and treasury reports.
Examiner
Issuance of the report according to the “General Law of Commercial Societies”.
Accounting
Our firm offers specialized accounting services, responding to any requirement in the international field.
Specialized accounting and specific requirements distinguish our firm as one of the best options in the market.
Due Diligence
We determine the purchase or sale value of a company based on the agreed formula between buyers and the sellers, assuring that the company’s value is sustainable.
We analyze the main areas that build value by increasing the company’s value through the VOP method (Value Opportunities Profile). Once the opportunities that a company has been detected, we work to increase the value of that company on a lapse of 18-24 months.
Transfer Price Studies
A high percentage of multinational activities are between related parties. Given the high level of control and transparency required by tax authorities worldwide, it is essential to comply with transfer pricing laws and regulations.
Consequently, we understand the companies’ need to comply with the transfer prices regulations, the current global scheme requests to optimize tax control and avoiding multinational companies´ risks. Therefore, we advise taxpayers to comply with such obligations within the legal framework through our transfer prices area.
- Carrying out transfer prices studies (national and foreign).
- Price determination for transactions between related parties.
- Strategies design aimed to the compliance in terms of transfer pricing.
- Comparable determination.
- Determination of the market interest rate for financing between related parties, whether national or foreign.
- Market value determination for leasing and/or purchase-sale of immovable property.
- Tax annexes filling in terms of transfer pricing.
Our services include the necessary advice to perform intercompany transactions precisely and transparently, always aiming for compliance and minimizing possible tax contingencies.
Electronic billing
Issuance of standard and special invoices with various supplements, reception payment supplements, withholding, and payment info is based on the law’s current requirements.
Taxes
We offer a variety of services in tax matters, including the following:
- Tax disposition analysis.
- Monthly and annual computation taxes.
- Coordination and execution of tax procedures.
- Checking of the correct compliance of obligations.
- Expert´s opinions according to the company´s needs.
- Reasoning and advanced prevention of the annual impact of the Tax Reforms.
- Specific topics training.
Payroll
We are in charge of computing payroll, regular (weekly, biweekly, fortnightly, and monthly) and extraordinary according to each company’s needs, willing to determine each employee’s payment derived from a working relationship. Likewise, we compute local and federal contributions from this computing.
Additional to the payroll compute, some others are derived, for example:
- Settlements and severance payments, including receipts.
- Attending and advising everything related to Social Security, Housing Fund, and Payroll Tax.
- Determining contribution basis salary for the effects of Social Security and employer contributions to Housing Fund.
- Presenting to Social Security the affiliate movements of the personnel and the Annual Statement of the Job Risk’s Insurance Premium.
- Travel expenses stamp and payroll-related concepts.
- Social charges provisions requested by the client.
- Annual Income Tax adjustment of each employee.
- Payroll Digital receipts reconcilements with the Income Tax informed by the company.
It is worth mentioning that all of our computes are made based on the Mexican legislation ethically, thoughtfully, and correctly.
REPSE
- Analysis of the company’s activity and purpose
- REPSE Registration
- Four-monthly ICSOE and SISUB notices
- REPSE registration renewal
National accounting systems
We work with the most prestigious national accounting systems:
- CONTPAQi
- COI
- ERP
- SAP Dynamics
Expatriate Tax Returns
We offer a comprehensive service of tax declarations for expatriates, ensuring compliance with tax obligations both in the country of origin and in the country of residence.
- Prepare and file tax returns in both countries.
- Analyze double taxation agreements to avoid double taxation.
- Providing tailored tax solutions.
- Keeping the clients informed about legislative changes that may affect them.