BERDO compliance for 2025 emissions now comes down to four dates. Boston’s Building Emissions Reduction and Disclosure Ordinance (BERDO) covers non-residential buildings of 20,000 square feet or more and residential buildings with 15 or more units. Buildings above 35,000 square feet face emissions standards from 2025. Smaller covered buildings start in 2030.
For a building over its limit, the City of Boston lists two routes still open. Buy Massachusetts (MA) Class I Renewable Energy Certificates (RECs) by 31 October 2026, or pay an Alternative Compliance Payment (ACP) of $234 for every metric ton of carbon dioxide equivalent (tCO2e) above the limit.
The flexibility window closed on 1 September
The City’s guidance, updated 2 September 2026, lists the Building Portfolio, Individual Compliance Schedule and Hardship Compliance Plan as closed. Applications were due on 1 September 2026. The Individual Compliance Schedule let owners with historic energy data set their own baseline, in return for a 50% cut in emissions by 2030 and 100% by 2050.
Owners who did not apply are measured against the published standard for their building use. A multi-use building can still opt in to the Blended Emissions Standard, which sets the limit by the size of each use.
RECs cut electricity emissions, not combustion
Only RECs from non-emitting sources count: solar, wind, small hydropower and geothermal. Biomass and landfill methane are excluded. For 2025 compliance, a REC must have been generated between 1 January 2024 and 30 June 2026.
The limit is structural. Eligible renewable energy can lower emissions from electricity use but not from fossil fuels burned on site. A laboratory or manufacturing building heated by gas boilers can buy RECs for every kWh it uses and still sit over its limit. The remaining overage is settled through ACPs.
BERDO compliance has four dates left in 2026
- 15 October 2026: annual reporting deadline for buildings with an approved extension.
- 31 October 2026: last date to buy MA Class I RECs through the City’s REC Connector Program, run with Green Energy Consumers Alliance, for 2025 emissions.
- 15 December 2026: Green Energy Consumers Alliance retires the RECs bought through the program.
- 31 December 2026: last date to send the City proof of retirement for RECs retired after the annual reporting deadline.
Owners buying outside the Connector Program should move early. Many brokers set minimum purchase volumes, so small orders may not be filled.
An ACP settles one year, not the next
An ACP clears the current compliance year. It does not change next year’s number. The $234 per tCO2e applies again every year the building stays over its limit, and the standards tighten every five years until they reach zero in 2050.
The durable fix is the gas load. That starts with a measured Scope 1 and 2 baseline and an ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers) Level II audit that sizes each combustion load. It ends with a heat pump or heat recovery design that can replace those loads before the 2030 step.
Split the 2025 overage before buying anything
Confirm the overage from verified data. BERDO requires third-party verification in the first reporting year and every five years after. Split the overage into its electricity and fossil fuel shares. Price RECs against the electricity share only. Treat the fossil fuel share as an ACP this year and a capital project for 2030.
The City’s free Building Decarbonization Advisor Program and Mass Save technical assistance can both feed a decarbonization plan. For US owners running Boston sites alongside European operations, the same Scope 1 and 2 baseline can serve both. Talk to our team before 31 October.
The 31 October deadline settles the electricity share of 2025 emissions and nothing else. Every tCO2e from gas stays on the ledger at $234 a year until the combustion load is removed.
