Mexico's annual operating report (COA): who files it, when and what it includes

The Cédula de Operación Anual (COA) is the instrument that feeds the Pollutant Release and Transfer Register (RETC), Mexico's national database of what each establishment releases to air, water and soil and what it transfers as waste or discharges. Its legal basis is the General Law of Ecological Balance and Environmental Protection (LGEEPA) and its RETC regulation.

For many plants the COA is also how other obligations are met: federal-jurisdiction fixed sources with an operating license file it as part of their air-quality regulation (air regulation, article 21), and large hazardous-waste generators submit their annual report through it (waste regulation, article 72).

Article 9 of the RETC regulation names these establishments as subject to federal reporting:

• Federal-jurisdiction industries listed in LGEEPA article 111 Bis: chemical, oil and petrochemical, paints and inks, automotive, pulp and paper, metallurgical, glass, power generation, asbestos, cement and lime, and hazardous-waste treatment, plus hydrocarbon-sector activities.
• Hazardous-waste generators, as the applicable regulations provide. The waste regulation requires large generators (10 metric tons or more a year) to submit their annual report through the COA.
• Facilities that discharge wastewater into receiving bodies that are national waters.

So checking the line of business isn't enough: you also need to check how much hazardous waste the plant generates and where its wastewater goes.

The federal COA is filed every year between March 1 and June 30 and reports operations from January 1 to December 31 of the previous year (RETC regulation, article 11). For example, between March and June 2027 you report 2026.

Article 10 of the RETC regulation defines the report's contents. In practice it is organized like this:

• General and administrative data: legal name, tax ID (RFC), location with coordinates, start of operations, headcount and work periods.
• General technical information: the process flow diagram, from incoming materials to every release, discharge or waste-generation point, with inputs, products and energy use.
• Air emissions: the equipment and activities that emit, stack and duct characteristics and, for pollutants regulated by NOM, the sampling results.
• Water: sources of extraction and discharge data, including discharges to the sewer.
• Hazardous waste: generator registration number, quantities generated, stored and transferred, and their treatment or final disposal.
• RETC substances: releases and transfers of the substances listed in NOM-165-SEMARNAT-2013 once their reporting thresholds are reached.
• Events and prevention: releases from accidents, leaks, spills, start-ups and shutdowns, and pollution-prevention and management actions.

The report is filed in the format SEMARNAT sets, through its online portal or the other options in article 12 of the RETC regulation. Keep each year's acknowledgment of receipt.

For the hazardous-waste report, the waste regulation (article 73) gives SEMARNAT 20 business days to review it and, once only, to ask you to complete, correct or clarify it within up to 15 business days. If you don't answer that request, the COA is treated as not filed.

• Reporting the wrong year: each year's COA covers the previous calendar year.
• Waste totals that don't match the same year's logbook and manifests.
• Mixing units: the waste report asks for quantities generated in units of mass (waste regulation, article 72).
• Reporting emissions without the sampling results the applicable NOMs require.
• Assuming a plant outside federal jurisdiction files nothing: being a large hazardous-waste generator or discharging into national waters also triggers the obligation.
• Leaving SEMARNAT's information request unanswered.

We work out which reports apply to you (federal, state or both), prepare a COA whose figures match your logbooks, manifests and sampling, and leave you a calendar of due dates. See our environmental permits and reports service or request a quote. If your question is about waste, also read the hazardous waste guide.