NYC Local Law 97 Emissions Limits

Who's covered

LL97 covers a building under any of three tests, per DOB's own program page: a single building that exceeds 25,000 gross square feet; two or more buildings on the same tax lot that together exceed 50,000 gross square feet; or two or more condominium buildings governed by the same board of managers that together exceed 50,000 gross square feet. "Exceeds" means exclusive -- exactly 25,000 or exactly 50,000 sq ft does not, on its own, trigger coverage.

The single-building threshold is identical to LL84's (25,000 sq ft), but the multi-building aggregation threshold is not -- and this is the single most counterintuitive fact in NYC's compliance-law stack. LL84's combined-lot and condo-aggregation rule requires more than 100,000 sq ft combined before it sweeps in buildings that don't individually clear 25,000 sq ft. LL97 uses the identical sweep-in mechanism but sets the bar at just over 50,000 sq ft combined -- half of LL84's. That means LL97's covered population is genuinely broader than LL84's for exactly the multi-building and condo scenario, not narrower or the same. See the dedicated section below for a worked example and what it means if you own a multi-building lot or a condo portfolio.

Tax lots are identified by BBL (Borough-Block-Lot); individual buildings on a lot by BIN (Building Identification Number). When buildings on a BBL together meet the 50,000 sq ft threshold, all buildings on that BBL become subject to LL97 -- but each one still has to demonstrate compliance under whichever specific section of the law applies to it, since not every building on a qualifying lot necessarily follows the same compliance pathway (see Key dates below).

Most covered buildings comply under Article 320. A separate track, Article 321, covers certain affordable housing and houses of worship -- income-restricted Mitchell-Lama buildings, buildings with a DOF tax exemption, buildings more than 35% rent-regulated, buildings in a project-based federal housing program, and buildings whose dominant occupancy is classified as a religious house of worship (occupancy group A-3, with its own verification forms). Article 321 compliance can be a one-time filing rather than an annual emissions-cap cycle, which is a materially easier obligation than what Article 320 buildings face -- worth confirming carefully if your building might qualify, rather than assuming the harder Article 320 path applies by default.

Key dates

May 1, every year -- the same headline date as LL84, and this is deliberate to flag: Article 320 required covered buildings to file their first report with DOB by May 1, 2025, and by May 1 of every year after. Article 321 buildings were also first required to submit their compliance report by May 1, 2025.

Filing goes through a dedicated portal -- BEAM, at nyc.beam-portal.org -- which is different from LL84's plain ESPM Share Request. BEAM draws on your ESPM energy data but the LL97 report itself is a distinct filing action inside a distinct system. (Watch for name confusion if you also own property in Chicago: Chicago's benchmarking program launched its own, unrelated support platform also branded "BEAM" in late 2025 -- same name, two unconnected systems, in two different cities.)

Which year an individual building's Article 320 emissions-limit obligations actually begin depends on its assigned compliance pathway -- most buildings are on Pathway 0, but DOB's dispute process recognizes three others:

Pathway	Article 320 obligations begin	Governing rule
0 (default)	2024	Standard Article 320 timeline
1	2026	Admin Code § 28-320.3.10.1
2	2035	Admin Code § 28-320.3.9
3	One-time compliance report only (Article 321)	Article 321, not Article 320

Layered on top of the pathway a building is on, the emissions limits themselves get meaningfully tighter over time: the caps that took effect in 2024 hold through 2029, then tighten substantially for the 2030-2034 compliance period, part of the city's stated goal of cutting covered buildings' emissions 40% by 2030 and reaching net zero by 2050. The exact numeric limit for a given building depends on its occupancy group under DOB rule 1 RCNY § 103-14 (last updated February 2023) -- we don't reproduce those per-occupancy-group coefficients here since they're granular and rule-specific, but the two-period structure (materially looser through 2029, materially tighter from 2030) is the fact every covered-building owner should plan around now, not in 2029.

Penalties

$268 per metric ton of CO2e over your building's annual emissions limit. The statute is direct: an owner whose report shows emissions exceeding the building's limit "shall be liable for a civil penalty of not more than an amount equal to the difference between the building emissions limit for such year and the reported building emissions for such year, multiplied by $268." This recurs every year the building stays over its cap, and unlike LL84's flat $2,000/year ceiling, there is no annual cap on this figure -- it scales with both the building's size and how far over the limit it runs.

A separate penalty applies for failing to file the report at all, independent of whether the building is over its cap -- $0.50 per square foot of gross floor area, for each month the violation goes uncorrected within the 12 months following the reporting deadline. Because every LL97-covered building is at least 25,000 sq ft, the floor on this penalty is substantial: a 25,000 sq ft building that stays unfiled works out to at least $12,500 for every month the violation continues past the point the penalty starts accruing.

But there's a real 60-day no-penalty window built into that same provision. The statute explicitly exempts an owner from this late-filing penalty "for a report demonstrating compliance with the requirements of this article if such report is filed within 60 days of the date such report is due" -- in effect, filing by roughly June 30 (60 days after May 1) draws zero penalty under this specific provision, even though the report is technically late. This is a genuinely different mechanic from LL84's quarterly-escalation structure, which has no equivalent penalty-free window.

Owners who formally engage a registered design professional can access a further filing extension to August 29 -- a real accommodation, but one that requires the RDP engagement to happen, not just an intention to eventually hire one.

False statements on a filing carry penalties of up to $500,000 -- a figure that exists specifically to deter gaming the certification process, since the entire compliance model depends on an RDP's attestation being trustworthy.

DOB also publishes dedicated penalty mitigation guidance for both Article 320 and Article 321 filers, and the law allows a limited set of deductions and alternatives that reduce a building's calculated emissions before any penalty math applies -- offsets (capped at 10% of the building's calculated emissions limit, currently limited to the Affordable Housing Reinvestment Fund offsets program), distributed energy resources (on-site or off-site solar or storage), beneficial electrification, and a few narrower categories like fuel cells and cogeneration. These require your RDP's involvement to apply correctly -- they're not a self-service checkbox.

Step-by-step: how to comply

1. Confirm your building's compliance pathway and Article. Most buildings are on the default Article 320, Pathway 0 timeline; affordable housing and houses of worship may qualify for Article 321's one-time filing instead. We check your building against the Covered Buildings List's compliance-pathway data and flag anything that looks like it might qualify for Article 321 or a later pathway -- but a pathway or Article dispute has to be filed by you (or on your authorization) through BEAM.
2. Gather the same 12 months of energy data underlying your LL84 benchmarking (if the building also files LL84) as the base for your emissions calculation, since LL97's numbers derive from the same underlying usage. We keep this data in sync across both filings once it's in our system, so you're not re-entering the same utility numbers twice.
3. Engage a New York-registered design professional to calculate emissions against your building's limit and prepare the certified report -- this sign-off is legally required, not optional. This is the one step no software platform can substitute for; we can help you identify and coordinate with an RDP, but the license-backed attestation has to be theirs.
4. File through BEAM (nyc.beam-portal.org) by May 1. If you're going to miss it, know that filing within 60 days (roughly by June 30) avoids the late-filing penalty entirely, and a formally engaged RDP can extend that further to August 29 -- but neither of those is a substitute for planning to hit May 1 in the first place, since the over-the-cap $268/tCO2e penalty is separate from (and unaffected by) the late-filing grace period.
5. If your building is projected to exceed its cap, work with your RDP on deductions, offsets, or capital planning before the penalty accrues, rather than treating the $268/tCO2e figure as a routine cost of doing business -- it recurs every year the building stays over.

How this interacts with Local Law 84 (read this even if you already read the LL84 guide)

Same May 1 deadline, genuinely different filings. LL84 and LL97 are typically due on the exact same calendar date, but they are not one combined filing -- LL84 goes through an ESPM Share Request to DOB; LL97 goes through the dedicated BEAM portal, with a mandatory RDP certification LL84 doesn't require. A building can be perfectly compliant with one and non-compliant with the other.

LL97's aggregation rule for multi-building lots and condos is broader than LL84's -- 50,000 sq ft combined, not 100,000. Concretely: three condo buildings on one tax lot at 20,000 sq ft each (60,000 sq ft combined, none individually over 25,000 sq ft) clear LL97's 50,000 sq ft aggregation trigger and are covered by LL97's emissions caps, while falling short of LL84's 100,000 sq ft aggregation trigger and owing no LL84 benchmarking report at all under that route. If you manage a multi-building lot or condo portfolio, don't assume "we don't have to benchmark" also means "we have no emissions obligations" -- check LL97's lower aggregation bar independently.

The penalty shapes are opposites in an important way. LL84's fine is flat and capped ($500/quarter, $2,000/year maximum, regardless of building size). LL97's is uncapped and size-and-severity-scaled ($268/tCO2e over the limit, plus a separate $0.50/sq ft/month late-filing exposure with its own 60-day grace window). A large building well over its emissions cap can face LL97 penalties many times larger than anything LL84 could ever assess.

Filing one does not satisfy the other, and being exempt from one does not exempt you from the other -- they're evaluated against their own, separately defined covered-building tests. See our LL84 guide for the benchmarking side, including the Class One and garden-style residential exemptions that don't have an LL97 equivalent.

What we handle

LL97 is the highest-stakes annual filing in NYC's building compliance stack, precisely because the penalty scales with both size and shortfall rather than being a flat fee. Run the compliance checker below to confirm your building's covered status under LL97's own tests (the 50,000 sq ft aggregation rule catches multi-building owners who assume LL84 status is a reliable proxy), then join the waitlist -- we track your BEAM filing status and keep your LL84 and LL97 energy data in sync. What stays yours: engaging and paying a registered design professional, and any capital or operational decisions about closing an emissions gap.

Frequently asked questions

Does LL97 replace the need to file LL84 benchmarking?

No. LL84 benchmarking and LL97 emissions reporting are separate, parallel obligations, each evaluated against its own covered-building test. A building required to do both must file both, every year -- one filing never substitutes for the other.

Can a building avoid the $268/tCO2e penalty just by paying it?

The $268/tCO2e figure functions as the effective cost of non-compliance, but it recurs annually for as long as the building stays over its cap -- it's best treated as an ongoing, compounding carrying cost rather than a one-time buy-out, since next year's report starts the calculation over again against that year's (likely tighter) limit.

Who is allowed to certify my LL97 report?

A New York-registered design professional (a PE or RA), or in limited cases a retro-commissioning agent, working under the Article 320 or Article 321 Professional Attestation Form as applicable. Self-certification by the owner is not an option.

What happens if I file late?

If you file within 60 days of the May 1 due date (roughly by June 30), the late-filing penalty under Admin Code § 28-320.6.2 doesn't apply at all. Past that window, the penalty is $0.50 per square foot of gross floor area for each month the violation remains uncorrected, up to 12 months. This is entirely separate from the $268/tCO2e over-the-cap penalty, which applies regardless of when you file.

My tax lot has three condo buildings, none over 25,000 sq ft, totaling 60,000 sq ft combined. Are we covered?

Yes, under LL97 -- your combined square footage clears LL97's 50,000 sq ft aggregation threshold for condominium groupings under the same board of managers, even though it falls short of LL84's 100,000 sq ft aggregation threshold. This is exactly the counterintuitive gap described above: you'd owe an LL97 emissions filing without necessarily owing an LL84 benchmarking filing through the aggregation route.

What deductions or offsets can reduce my building's calculated emissions?

A limited, RDP-administered set: offsets (capped at 10% of your building's calculated emissions limit, currently limited to Affordable Housing Reinvestment Fund offsets), distributed energy resources like on-site or off-site solar or storage, beneficial electrification, and narrower categories including qualifying fuel cells and cogeneration systems. None of these are self-service -- they go through your registered design professional as part of the certified report.

Is Article 321 easier than Article 320?

For buildings that qualify (certain affordable housing and houses of worship), yes -- Article 321 can be a one-time compliance report rather than an annually recurring emissions-cap filing. It's worth explicitly checking whether your building's ownership or use profile qualifies before assuming the harder Article 320 annual cycle applies by default.