Local Law 97: Greenhouse Gas Emissions Limits

Updated for 2025 — Local Law 97 (LL97) is one of the most ambitious pieces of climate legislation in New York City history. Enacted under the Climate Mobilization Act, LL97 sets legally binding limits on greenhouse gas (GHG) emissions for large buildings. The first wave of enforcement begins in 2025, with escalating thresholds in future years.

If you own or manage a covered building, now is the time to assess your emissions profile and create a plan for compliance. Failing to act could result in significant penalties—and missed opportunities to future-proof your asset.

What Is Local Law 97?

LL97 targets energy-related emissions from buildings, which account for nearly 70% of NYC’s carbon footprint. The law establishes annual carbon emissions caps based on building use type and square footage.

The legislation applies to a wide range of building categories, including commercial, residential, institutional, and mixed-use properties. The goal is to push building owners toward energy efficiency, electrification, and sustainable upgrades.

Who Must Comply with LL97?

LL97 applies to:

Buildings 25,000 square feet or larger
Two or more buildings on the same lot that together exceed 50,000 square feet
Condo/co-op associations with a combined total floor area exceeding 50,000 square feet

Covered buildings include offices, retail centers, schools, hospitals, multifamily buildings, and more. Religious institutions and certain income-restricted housing may receive limited exemptions or alternate pathways.

Compliance Timeline for 2025

May 1, 2025 – First annual emissions report due to the NYC Department of Buildings
June 30, 2025 – Grace period ends; reports submitted by this date will not be fined
August 29, 2025 – Extended deadline if an official extension is requested by June 30

To qualify for the August extension, building owners must submit an extension request to DOB before the June 30 deadline. Reports submitted after August 29, or without a valid extension, may be subject to penalties.

Key Requirements of LL97

To comply with Local Law 97, building owners must:

Calculate building emissions
Use the formula outlined by DOB and apply emissions factors to each energy type (electricity, natural gas, steam, etc.). Emissions are measured in metric tons of CO₂e per square foot.

Compare emissions to building-specific limit
Each occupancy group (e.g., office, hotel, multifamily) has its own emissions threshold. Your building’s use classification and size determine your cap.

Submit an annual emissions report
Starting in 2025, owners must submit a certified report prepared by a registered design professional. This report must confirm compliance or calculate any excess emissions.

Pay fines for exceeding caps
Owners must pay $268 per metric ton of CO₂e emissions that exceed their annual cap.

Pursue emissions-reduction strategies
This may include:

Battery storage or demand response
HVAC upgrades
Envelope insulation
Building electrification
On-site renewable energy
Load shifting or peak shaving
Battery storage or demand response

Why LL97 Matters

Benchmarking offers visibility into operational performance and helps building owners and managers make informed capital planning decisions. It’s Local Law 97 is not just another building regulation—it represents a shift toward a carbon-accountable real estate market. LL97 will:

Drive capital investment toward decarbonization
Influence asset valuation and ESG risk profiles
Affect tenant retention, especially in sustainability-conscious industries
Shape long-term operational strategies and utility planning

Failure to comply may result in DOB violations and steep penalties. Building owners who exceed their emissions limits will be fined $268 per metric ton of CO₂e over the cap—which can quickly add up to tens or hundreds of thousands of dollars annually. In addition, failing to file the required emissions report by the May 1 deadline can result in a fine of $0.50 per square foot per month. There is a grace period through June 30, but reports submitted after that will be retroactively fined from May 1 onward.

Non-compliance can also make your property ineligible for energy incentives, sustainability certifications, or green financing opportunities, impacting both operational costs and marketability.