In 2012, Mexico enacted the General Law on Climate Change (GCCL), which required the creation of a national registry for greenhouse gases and provided orientation to federal, state and municipal authorities toward the authority to establish a voluntary emissions trading scheme (ETS). ( Mexico will launch a pilot national emissions trading scheme in Aug. 2018 with a three-year pilot phase. The pilot is scheduled to last 36 months, between 1 January 2020 and 31 December 2022. "The pilot will cover the energy and industry sectors. Energy encompasses both electricity generation and fossil-fuel extraction and production. Industry includes, among others, the automotive, cement, chemicals, glass, steel, metallurgical, mining, and petrochemicals subsectors, as well as the pulp and paper subsector. Only direct CO2 emissions will be regulated through the pilot, and participation is limited to entities with annual emissions greater than 100,000tCO2. The system is expected to cover around 300 entities in this phase, corresponding to approximately 45% of national emissions." (ICAP 2019)

New Developments: In 2017, Mexico began a simulation of a voluntary Emissions Trading Scheme (ETS) and the General Climate Change Law makes the scheme mandatory as soon as its three-year pilot phase concludes. The pilot phase—originally planned to start in August 2018—started operation in January 2020. The ETS will not replace the existing carbon tax.