Local Law 97
Carbon emissions limits for NYC buildings under the Climate Mobilization Act. Understand which buildings are covered, emissions thresholds by building type, penalties for non-compliance, and how to prepare.
What Local Law 97 Requires
Local Law 97 of 2019, part of the landmark Climate Mobilization Act, sets greenhouse gas emissions limits for buildings over 25,000 gross square feet in New York City. It is one of the most ambitious building emissions laws in the world, covering approximately 50,000 properties and targeting an 80% reduction in building emissions by 2050.
The law requires building owners to track and report their annual carbon emissions and stay within prescribed limits based on building occupancy type. Buildings that exceed their limits face significant financial penalties assessed on a per-ton basis.
LL97 directly addresses the fact that buildings account for nearly 70% of New York City's greenhouse gas emissions, making them the single largest contributor to the city's carbon footprint.
Who Must Comply
Local Law 97 applies to most buildings in New York City that exceed 25,000 gross square feet. This includes:
- Commercial office buildings — The majority of Manhattan office stock exceeds the threshold
- Residential buildings — Multifamily buildings over 35,000 square feet (roughly 35+ units)
- Mixed-use properties — Condos, co-ops, and mixed commercial-residential buildings
- Institutional buildings — Hospitals, schools, hotels, and houses of worship (with some exemptions)
Exemptions: City-owned buildings, certain rent-regulated affordable housing complexes, industrial facilities covered by the EPA emissions trading system, and houses of worship (for their primary worship space) may be exempt or have modified requirements.
Emissions Thresholds by Period
LL97 sets emissions limits in two compliance periods, with progressively stricter caps. Limits are measured in metric tons of CO2 equivalent per square foot per year (tCO2e/sf/yr):
- 2024-2029 (Period 1) — Initial limits designed to target the worst-performing buildings. Office buildings: 8.46 kgCO2e/sf/yr. Multifamily residential: 6.75 kgCO2e/sf/yr. These limits affect roughly 20% of covered buildings.
- 2030-2034 (Period 2) — Significantly stricter limits. Office buildings: 4.53 kgCO2e/sf/yr. Multifamily residential: 3.35 kgCO2e/sf/yr. These limits will affect the majority of covered buildings.
Each building's specific limit depends on its occupancy group classification. Buildings with multiple occupancy types calculate a blended limit based on the square footage allocated to each use.
Penalties for Exceeding Limits
Buildings that exceed their emissions limits face a civil penalty of $268 per metric ton of CO2 equivalent over the limit, assessed annually. There is no cap on penalty amounts.
- Small office building (50,000 sf) — Could face penalties of $50,000-$150,000 per year if significantly over the limit
- Large office tower (500,000 sf) — Could face penalties exceeding $1 million per year in the 2030 compliance period
- Multifamily residential — Older buildings with steam heat and poor insulation are most at risk, with potential penalties in the tens of thousands annually
Beyond direct penalties, non-compliance may affect property values, insurance costs, and tenant retention as corporations increasingly seek low-carbon workspaces. Penalties are expected to be enforced starting at the end of the first compliance period in 2029.
How to Prepare for Compliance
Building owners should take a proactive approach to LL97 compliance. Key steps include:
- Benchmark your building — Use EPA Energy Star Portfolio Manager to track energy consumption and calculate your current emissions against LL97 limits
- Conduct an energy audit — A Local Law 87 energy audit identifies the most cost-effective efficiency improvements for your building
- Upgrade building systems — Replace aging boilers, improve insulation, install LED lighting, upgrade windows, and consider electrification of heating systems
- Explore renewable energy — Rooftop solar, renewable energy credits (RECs), and power purchase agreements can offset grid electricity emissions
- Plan capital improvements — Many upgrades require significant investment. Start planning now for the stricter 2030 limits, as capital improvement cycles often span 3-5 years
Reporting Requirements
Building owners must submit annual emissions reports to the NYC Department of Buildings demonstrating their compliance status. Key reporting requirements include:
- Annual benchmarking — Energy consumption data must be reported through EPA Energy Star Portfolio Manager by May 1st each year (already required under Local Law 84/133)
- Emissions calculation — Total building emissions must be calculated using prescribed coefficients for each fuel type, including electricity, natural gas, fuel oil, and steam
- Compliance documentation — Buildings must maintain records of energy efficiency improvements, renewable energy purchases, and any deductions or adjustments claimed
- Alternative compliance — Buildings may apply for alternative compliance pathways, including prescriptive measures and greenhouse gas offsets, subject to DOB approval
Failure to file required reports carries its own penalties separate from emissions exceedance penalties. Building owners should ensure they have systems in place to track and report energy data accurately.
How KomplyOS Helps
Stop tracking compliance in spreadsheets. KomplyOS automates deadlines, scheduling, and filing so nothing falls through the cracks.
Frequently Asked Questions
What buildings are covered by Local Law 97?
Local Law 97 applies to most buildings in New York City over 25,000 gross square feet. This includes office buildings, residential buildings with more than 35,000 square feet, and certain other occupancy types. Some exemptions exist for city-owned buildings, houses of worship, rent-regulated affordable housing (with limitations), and industrial facilities covered by the EPA emissions trading system.
What are the penalties for exceeding emissions limits?
Building owners who exceed their carbon emissions limits face a penalty of $268 per metric ton of CO2 equivalent over the limit, assessed annually. For a large office building, this could mean penalties of hundreds of thousands of dollars per year. The first compliance period (2024-2029) has more lenient limits, with stricter thresholds beginning in 2030.
How do I calculate my building's carbon emissions?
Building emissions are calculated based on energy consumption data from utility bills. Each fuel type has a specific emissions coefficient: electricity uses a grid-based coefficient, natural gas uses a fixed coefficient per therm, and other fuels (oil, steam, district chilled water) each have their own factors. The total emissions in metric tons of CO2 equivalent are then compared to the building's limit, which is based on occupancy type and gross floor area.
How does Local Law 97 relate to Local Law 87?
Local Law 87 requires energy audits and retro-commissioning for buildings over 50,000 square feet every ten years. While LL87 focuses on identifying energy efficiency opportunities, LL97 sets mandatory emissions caps with financial penalties. The two laws work together: the audits and improvements identified under LL87 directly help buildings meet their LL97 emissions limits. Compliance with LL87 is a practical pathway to LL97 compliance.
What is the timeline for Local Law 97 compliance?
Local Law 97 has two main compliance periods. The first period runs from 2024 through 2029 with initial emissions limits. The second period begins in 2030 with significantly stricter limits designed to put buildings on a path to 80% emissions reduction by 2050. Buildings must report their emissions annually and will be assessed penalties at the end of each compliance period if they exceed their limits.
Related Compliance Guides
Local Law 87 — Energy Audits
Energy audit and retro-commissioning requirements for large buildings.
Local Law 11 — Facade Inspections
FISP requirements for buildings over 6 stories.
Local Law 152 — Gas Piping Inspections
Gas piping inspection requirements and GPS-2 filing.
NYC Compliance Calendar
All 2026 NYC building compliance deadlines in one place.
Never Miss a Compliance Deadline
KomplyOS tracks every building compliance requirement across the tri-state area automatically. Contact us to see how much time you save.