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Office of Energy & Sustainable Development (OESD)
Office of Energy & Sustainable Development (OESD)

Building Emissions Saving Ordinance (BESO)

Please submit your BESO application and filing fee through the Online BESO Application Portal. If you have any questions, email the BESO Helpdesk at

As of July 1st, 2021, buildings less than 25,000 square feet will need to be complete a BESO assessment prior to listing the building for sale. Please see the following PDF for information on the new Time of Listing process

Energy use in our homes and commercial buildings is the second leading contributor of greenhouse gases in the City of Berkeley making up 38% of our overall greenhouse gas emissions with 31% of Berkeley's citywide emissions coming from natural gas, according to Berkeley's latest green house gas inventory.

BESO requires building owners and homeowners to complete and publicly report comprehensive energy assessments to uncover energy and GHG emissions saving opportunities. The assessments are conducted by registered energy assessors (for Commercial, Multifamily & Mixed Use or Houses [1-4 unit residential buildings]) who provide tailored recommendations on how to save energy, eliminate fossil fuels and link building owners to incentive programs for energy efficiency and electrification upgrades (for residential see; for multifamily see Energy efficiency improvements and electrification recommendations are voluntary and encouraged. BESO is required prior to sale of a house or whole building under 25,000 square feet, and on a 5-year reoccurring cycle for large multifamily and commercial buildings.

BESO Requirements:

  Building Type/Size   New Requirements
 1-4 unit Homes  • Assessment at time of listing (July 1, 2021)
 850 - 14,999 ft2  • Assessment at time of listing (July 1, 2021)
 15,000 - 24,999 ft2  • Assessment at time of listing (July 1, 2021)
 • Annual benchmarking (Summer 2022)
 25,000 ft2 or more  • Assessment every 5 years
 • Annual benchmarking

  How to Comply with BESO: 

 BESO Time of Listing Button  BESO Assessor Icon
BESO Large Building Requirements  BESO How to Benchmark Icon


 Links to BESO Documents   

(Refer to BESO Large Building Requirements for buildings over 25,000 ft2) 

 BESO Checklist Small Icon  Online BESO Application Portal* for under 25,000 ft2 
  • Check Compliance Status
  • Submit BESO application and filing fee
  • Retrieve Copy of Compliance Form
  • Download BESO Assessment and Fuel Source Disclosure
BESO Assessor Small Icon  Registered Energy Assessor Lists:
  *Visit the BESO Time of Sale page for more information.


To learn more about ways to save energy, lower utility bills, and improve the comfort of your home, please see our Energy Efficiency Incentive Programs page.  Participation in one of these verified programs may qualify you for a High Performance exemption.   

BESO Governing Documents:

BESO Resources:

 For questions, email


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Office of Energy & Sustainable Development (OESD), 1947 Center Street, 1st Floor, Berkeley, CA 94704
Questions or comments? Email: Phone: (510) 981-7465
(510) 981-CITY/2489 or 311 from any landline in Berkeley
TTY: (510) 981-6903