Last updated: June 9, 2026. By Will Tygart. Every factor in the calculator below was extracted from the current consolidated text of 1 RCNY 103-14 and verified against the rule on June 9, 2026.
A Local Law 97 fine is calculated in one line: (your building’s actual annual emissions − its emissions limit) × $268 per metric ton of CO2e, assessed every year you remain over the cap. The limit is your gross floor area times a published factor for your property type — 0.00758 tCO2e per square foot for an office today, falling to 0.002690852 in 2030. The separate failure-to-file penalty is gross floor area × $0.50 per month. Use the calculator below for your building, then read the part nobody’s calculator shows you: what the 2030 factors do to a building that is comfortably compliant today.
LL97 Penalty Calculator — emissions factors as printed in 1 RCNY 103-14(c)(3); penalty rate $268/tCO2e per Admin Code §28-320.6.
Estimates only. Mixed-use buildings use square-footage-weighted factors; for 2024–2025 owners could elect the statutory occupancy-group limits instead; good-faith-efforts mitigation, RECs, AHRF offsets, and the disaster provision can reduce penalties. Always confirm against 1 RCNY 103-14 and your Registered Design Professional.
The formula, worked by hand
Take a 60,000 sq ft Midtown office building:
- Limit today: 60,000 × 0.00758 = 454.8 tCO2e/year
- If it emits 550 tCO2e: (550 − 454.8) × $268 = $25,514/year
- If it never files: 60,000 × $0.50 = $30,000/month — one month of silence costs more than a year of being 21% over the cap. Whatever else is true about your building, file.
The 2030 cliff, in numbers nobody publishes
Most LL97 coverage says the 2030 limits get “roughly 40% stricter.” The actual factors in the rule (1 RCNY 103-14(c)(3)(iii)) are far more dramatic for some property types:
| ESPM property type | 2024–2029 factor | 2030–2034 factor | Reduction |
|---|---|---|---|
| Office | 0.00758 | 0.002690852 | −65% |
| Multifamily Housing | 0.00675 | 0.003346640 | −50% |
| Hotel | 0.00987 | 0.003850668 | −61% |
| Retail Store | 0.00758 | 0.002104490 | −72% |
| Non-Refrigerated Warehouse | 0.00426 | 0.000883187 | −79% |
| Hospital | 0.02381 | 0.007335204 | −69% |
| Data Center | 0.02381 | 0.014791131 | −38% |
| Restaurant | 0.01181 | 0.004038374 | −66% |
| K-12 School | 0.00675 | 0.002230588 | −67% |
| Medical Office | 0.01074 | 0.002912778 | −73% |
(Factors are tCO2e per square foot per year, as printed in the rule. The 2030 table also cuts the grid-electricity coefficient roughly in half — to 0.000145 tCO2e/kWh — reflecting expected grid cleanup, which softens the blow for electrified buildings specifically.)
What that does to a real building: the same 60,000 sq ft office emitting 400 tCO2e is comfortably under its 454.8-ton cap today — penalty $0. In 2030 its cap drops to 161.5 tons. Same building, same energy use: 238.5 tons over, $63,931 per year, every year. That is why Urban Green’s finding — only ~9% of properties exceed today’s caps but ~57% exceed the 2030 caps — is the single most important number in NYC real estate planning, and why a “we’re compliant” answer in 2026 is only half an answer.
The fines-versus-retrofit math, honestly
Some owners are paying. Habitat’s reporting quotes a senior official at a prominent real estate firm: eliminating the fines would mean investing “15 to 20 times the fine amount,” and an energy manager’s example pits an $8–10M retrofit against a ~$180,000-a-year penalty (Habitat, March 2025). For 2026, that arithmetic can be rational.
It stops being rational on three clocks. First, fines repeat annually, forever — a $180K/year penalty is $1.8M over a decade against a one-time retrofit. Second, the 2030 factors multiply the overage: the building paying $180K today may be paying three to five times that from 2030. Third, equipment dies on its own schedule anyway — the cheapest compliance is the boiler you were already replacing, replaced electric, with beneficial-electrification credits that are richest before December 2026. REBNY projects citywide fines approaching $900 million a year once the 2030 limits bite — the buildings that avoid contributing to that number are the ones doing the math now, while the retrofit can ride the capital calendar instead of fighting it.
Five things that legitimately reduce an LL97 penalty
- Good-faith-efforts mitigation (1 RCNY 103-14(i)(2)) — requires a filed report, current LL84 benchmarking, and LL88 attestation, plus a qualifying path such as an RDP-certified decarbonization plan or an approved application for compliance work.
- RECs — offset electricity-attributable emissions only, must be NYC-deliverable, currently uncapped (decarbonization-plan filers excluded); Zone J Tier 4 supply (CHPE, Clean Path NY) becomes materially available during 2026.
- AHRF offsets — capped at 10% of your limit, priced at $268/ton (deliberately equal to the penalty), funding affordable-housing decarbonization.
- The disaster provision (1 RCNY 103-14(i)(1)) — documented hurricane, severe flooding, or fire damage that precluded compliance can zero the year’s penalty. Your restoration contractor’s job file is the evidence; see what LL97 does and does not count.
- Mediated resolution — a negotiated DOB compliance plan in lieu of penalty, case by case.
What this means for each seat at the table
| If you are the… | The penalty math says… |
|---|---|
| Owner | Run the calculator twice — today’s factor and 2030’s. The second number belongs in the capital plan and the next refinancing conversation, because lenders are already running it. |
| Facility / property manager | Your energy data is the input to a six-figure equation. Tight ESPM records, submetering, and vendor documentation are what make the difference between an estimated overage and a defended one. |
| Tenant | Your consumption is inside the building’s number, and lease structures increasingly pass LL97 exposure through. A tenant who can demonstrate efficiency is negotiating leverage; one who cannot is a cost center. |
Frequently asked questions
How are Local Law 97 fines calculated?
(Actual annual building emissions − the building’s emissions limit) × $268 per metric ton CO2e, assessed annually. The limit is gross floor area × the published factor for your ESPM property type — 0.00758 tCO2e/sqft for offices in 2024–2029, dropping to 0.002690852 in 2030.
How much is the LL97 penalty per ton?
$268 per metric ton of CO2e over the limit, per year. The Affordable Housing Reinvestment Fund offset is deliberately priced at the same $268 — the city set the escape hatch at exactly the cost of the penalty.
What is the penalty for not filing an LL97 report?
Gross floor area × $0.50 per month, retroactive to May 1 of the filing year. On a 60,000 sq ft building that is $30,000 a month — typically far worse than the overage penalty itself.
When do LL97 fines start?
They already have: caps took effect January 1, 2024, first reports were due in 2025, and DOB confirmed in April 2026 that ~1,400 non-filers are in the enforcement pipeline with OATH cases in preparation. The much larger fine wave arrives with the 2030 limits, which roughly 57% of covered buildings currently exceed.
How much stricter do LL97 limits get in 2030?
It depends on property type: offices drop 65%, retail 72%, warehouses 79%, multifamily 50%, data centers 38% — per the factors printed in 1 RCNY 103-14(c)(3)(iii). A building comfortably compliant today can face a six-figure annual penalty in 2030 at the same energy use.
Is there an official LL97 penalty calculator?
DOB publishes the factors and formula but no official calculator; NYC Accelerator’s Building Energy Snapshot is the closest city tool. The calculator on this page applies the rule’s printed factors directly and shows both compliance periods side by side.