What does Local Law 97 cost your building?
Local Law 97 gives every New York City building over 25,000 square feet an annual carbon budget, and charges $268 for every metric ton above it. Enter an address and Seayora reads what that building already reported to the City, works out its cap from its actual occupancy mix, and shows the penalty for the current compliance period and for the far tighter caps that begin in 2030. No account, no email, and the estimate is refused rather than guessed when the City has no data for the building.
How a building's carbon cap is set
Each occupancy type carries an emissions limit per square foot set by the City, and a building's annual cap is the sum across its uses — not one blended rate. A building with apartments above ground-floor retail and a parking garage has three different limits contributing to one cap, and storage and parking are capped far more tightly than housing. Getting that mix wrong is the most common way an LL97 estimate goes badly wrong in either direction.
The caps tighten sharply in 2030
The 2024–2029 limits are the lenient ones. From 2030 they fall by roughly half for most building types — the multifamily limit drops from 0.00675 to 0.00334664 tCO2e per square foot. A building comfortably compliant today can face a six-figure annual penalty in 2030 having changed nothing at all, because the cap moved rather than the emissions.
Failing to file is a separate penalty
The annual emissions report is due 1 May for the previous calendar year and must be certified by a registered architect or professional engineer licensed in New York State. Failing to file costs $0.50 per gross square foot per month, entirely separate from and on top of any penalty for exceeding the cap. A building can owe both at once.
The four ways to reduce what you owe
- Efficiency retrofits — envelope sealing, heating controls, steam traps and lighting, generally the cheapest tonne of carbon in a pre-war building
- The beneficial electrification credit for qualifying heat pumps energized before 2030 — worth double if energized before 2027, and requiring a coefficient of performance of at least 1.5 at 5°F, so resistance heating earns nothing
- Renewable energy credits, which reduce reported emissions but only where the generation is delivered into New York City
- A decarbonization plan and good-faith-effort filing, which can mitigate the penalty for an owner who commits real capital — renewable energy credits cannot be counted toward it
Rent-regulated buildings follow Article 321 — until 2035
A building where more than 35% of dwelling units are rent-regulated follows Article 321 instead: a prescriptive list of energy measures rather than an emissions cap, with no per-ton penalty. Seayora does not quote cap math for those buildings, because doing so could drive an unnecessary retrofit. That carve-out ends after 2034 — from 2035 those buildings are assessed against a standard cap like any other covered building.
What this calculator is, and is not
It is an estimate built from public data: NYC Local Law 84 benchmarking, which is the building's own reported energy use, and PLUTO for floor area and year built. It is not a certified emissions report, legal advice, or an engineering assessment, and the occupancy mix it infers from benchmarking use types may differ from the building's actual classification. Seayora packages the data a filing needs; the filing itself must be certified by a registered design professional.