Overview
Introduced: 2019
Effective from: January 1, 2024
Last modified: June 2024 (latest DOB guidance)
Region(s): New York City, USA
About
Local Law 97 (LL97) is the cornerstone of New York City’s Climate Mobilization Act, one of the most ambitious climate policies globally. The law establishes legally binding carbon emissions caps for most buildings over 25,000 square feet, aiming to cut NYC’s building emissions by 40% by 2030 and reach net-zero by 2050.
Buildings are the city’s largest source of greenhouse gas emissions—responsible for over two-thirds of the city’s total—and LL97 is designed to transition real estate toward clean energy, energy efficiency, and long-term sustainability.
Criteria for compliance
LL97 applies to the following property types within NYC:
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Single buildings ≥ 25,000 square feet
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Multiple buildings on the same tax lot totaling ≥ 50,000 square feet
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Multiple buildings governed by a single condo/co-op board totaling ≥ 50,000 square feet
Exemptions / Special Provisions:
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NYC Housing Authority (NYCHA) buildings
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Houses of worship
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Rent-regulated buildings (≥35% units) qualify for alternative compliance pathways focused on prescriptive upgrades
Compliance timelines
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2024–2029: First compliance period — limits apply to the top 20% of the most carbon-intensive buildings
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2030–2034: Tighter carbon caps apply to all covered buildings
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2035–2050: Progressive emission reductions targeting net-zero by 2050
*Buildings must report annually. First reports were due May 1, 2025, covering 2024 performance.
Prescriptive Energy Conservation Measures (PECMs)
- The Department of Buildings (DOB) has made available the Article 321 Workbook for Reporting Prescriptive Energy Conservation Measures, along with a template for the documentation of four PECMs.
- The completed template must be uploaded for each covered building by May 1, 2025.
Reporting requirements
All covered buildings must:
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Measure emissions annually using the NYC Department of Buildings’ (DOB) carbon coefficient methodology
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Report energy use and emissions through the DOB’s online system
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Stay below capped emissions limits based on property type and building area (kg CO₂e per sq. ft.)
Flexibility and alternatives
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Energy efficiency upgrades
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On-site clean energy systems (e.g., solar)
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Purchase of eligible Renewable Energy Credits (RECs) to offset emissions from electricity
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GHG offsets for limited compliance flexibility (subject to future rule making)
Third-party auditing
All reported data must be verified and certified by a Registered Design Professional (RDP) — either a Professional Engineer (PE) or Registered Architect (RA).
The NYC Office of Building Energy and Emissions Performance within NYC’s Department of Buildings oversees enforcement, compliance tracking, and public disclosure.
Penalties for non-compliance
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Exceeding emissions cap: $268 per metric ton of CO₂e over the annual limit
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Failure to file report: $0.50 per building square foot per month, until filing is complete
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False or misleading reporting: Subject to further fines and legal liability
Legal challenges
A state appellate court recently revived a lawsuit challenging Local Law 97, arguing that the law might conflict with the New York State Climate Leadership and Community Protection Act (CLCPA). This lawsuit raises concerns about the law’s future, although the City of New York is continuing to enforce it while the legal proceedings continue.
