DOB 101 for NYC Contractors: Everything You Need to Know in 10 Minutes

If you are newly licensed in New York City, or starting a business and taking your first jobs, or working with a new crew for the first time, you are walking into one of the most aggressive and confusing enforcement environments in the country. The paperwork is split across two systems. The violations live in three different databases. The agencies have overlapping jurisdictions. And the cost of getting it wrong starts at $2,500 and climbs fast.

This guide takes ten minutes to read and will save you from the most common mistakes new contractors make. No jargon without explanation, no acronyms without a translation, no fluff.

The Three Agencies You Will Deal With

Everything that can go wrong for you as a contractor in NYC flows through one of three agencies. Know what each of them does and you are already ahead of most of the field.

DOB (Department of Buildings). This is the agency that issues permits, enforces the NYC construction code, inspects jobsites, and writes most of the violations you will see. Think of DOB as the agency that decides whether you can do the work and whether you are doing it correctly. If you are a mechanical, plumbing, electrical, or general contractor, DOB is your primary regulator. Every permit you pull, every job you file, and every inspection you fail or pass runs through DOB.

HPD (Housing Preservation and Development). HPD handles residential buildings, specifically the habitability and maintenance side. If you are working in a residential building and your job creates a hazard for the tenants, HPD can issue its own violations on top of whatever DOB does. HPD violations are rated Class A, B, or C, with Class C being hazardous conditions that must be fixed immediately. If you touch multifamily residential work, you need to check HPD too.

OATH (Office of Administrative Trials and Hearings). This is the court. When DOB issues you an ECB summons, the hearing happens at OATH. OATH is where you either show up and contest the violation, or fail to show up and get hit with a default judgment at the maximum penalty. The old name for this court was ECB, and you will still hear people call it that. Either way, OATH and ECB refer to the same tribunal at 66 John Street.

ECB stands for Environmental Control Board, which was the name before the city consolidated its administrative courts under OATH. When you see “ECB violation” it means a summons that will be heard at OATH. When you see “ECB case number” it is the OATH docket number. Same thing, different vintage.

The Two Databases: BIS and DOB NOW

If DOB and OATH and HPD are the agencies, BIS and DOB NOW are where the data lives. You need to check both for any serious job. Here is why there are two of them and what lives in each.

BIS (Buildings Information System). The legacy system. BIS is old, it looks like a 1990s website, and it holds the historical record for every building and every contractor in NYC going back decades. If a violation was issued before 2020, it is almost certainly only in BIS. If a contractor had a license issued twenty years ago, the history is in BIS. If a building has an old Certificate of Occupancy, it is in BIS. BIS is clunky but comprehensive for anything older than a few years.

You access BIS at a810-bisweb.nyc.gov. No login required for the public-facing side. The five main tabs you will use are:

1. Property Profile. Type in an address or BIN. You get the building's basic info, its certificate of occupancy, any open complaints, and a link to the violation history.
2. Violations. Every ECB, DOB, and HPD violation ever issued against the property or its owner.
3. Complaints. Every DOB complaint filed, including the disposition code that tells you what happened after the inspector visited.
4. Jobs. Every job filed against the building going back decades. Shows who pulled the permit, the scope, and the current status.
5. Licenses. If you look up a contractor license number directly, you get license status, insurance coverage, and disciplinary history.

DOB NOW. The modern system. DOB NOW launched in 2020 and is now the mandatory filing system for most permit types. If you pull a permit today, you do it in DOB NOW. If you check the status of an active job, you check DOB NOW. If you pay a fee, you pay it in DOB NOW. BIS cannot be used for new filings. DOB NOW is where active permits, current job status, and recent filings live. It requires a login if you want to file anything, but the public portal is free to browse.

The critical insight: neither system is complete on its own. BIS has the history. DOB NOW has the current state. If you check only DOB NOW before taking a job, you might miss an old default judgment from 2018 that is still unpaid. If you check only BIS, you might miss that a new violation was issued last week. You need both.

The 5 Things to Check Before You Bid Any Job

Here is the exact checklist that experienced NYC contractors run before agreeing to take a job. Ten minutes of research can save you tens of thousands of dollars. Do not skip this for a residential job just because it feels informal. Do not skip it for a repeat client just because they seem fine.

1. Open violations at the property

Pull up the property in BIS Property Profile, click the Violations tab, and look at the list. Red flags include more than 5 open DOB violations, any open ECB violations with unpaid balances, any recent Stop Work Orders (even if now lifted), and HPD Class C hazardous violations.

Open violations on a property are not automatically your problem, but they become your problem the moment you sign a permit and file a job. Inspectors who respond to a new job at a problem property tend to look at everything while they are there. You also inherit a reputation risk: if this building is on the DOB's radar, your permits are on the radar too.

2. Recent 311 and DOB complaints

The Complaints tab in BIS shows every DOB complaint filed against the property. The pattern matters more than any single complaint. If the same address has had 8 complaints in the past year, there is something going on at that site and you are about to walk into it. Look at the disposition codes. A4 means a summons was issued. I3 means the work stopped and self-corrected. I1 means no violation was found after inspection. A string of A4s is a warning sign.

311 complaints feed into DOB within 1 to 3 days. If you see a high-priority 311 complaint from a week ago with no disposition yet, the inspector is coming this week. You are about to arrive at a jobsite with an inspector already on the calendar.

3. Active permits and their status

Check DOB NOW for active permits at the address. You are looking for two things. First, is there already an active permit for similar work? If so, someone is already doing this job and there may be a scope conflict. Second, are the permits current? Permits that expired and were never renewed often indicate work that was started and abandoned, and the city remembers.

4. Past OATH hearings and outcomes

Search the OATH hearings database by the building address or the owner's name. You are looking for default judgments (they indicate the owner does not show up to hearings) and repeat summonses (they indicate a pattern of enforcement). If the building has 3 defaulted ECB summonses, you are taking a job at a property the city considers a bad actor, and the next inspector will remember.

5. HPD housing violations (residential only)

If the building has residential units, check HPD's HPDONLINE system at hpdonline.hpdnyc.org. You are looking for Class C hazardous conditions (lead paint, no heat, structural) and Class B (less urgent). If HPD has an active Class C at the address, the tenants are already upset, and they are the most likely source of the next 311 complaint. Any job you do becomes part of the political fight between the landlord and the tenants.

What to Do When You Spot Red Flags

Spotting problems on a property does not always mean you walk away. It means you charge appropriately and document aggressively. Specifically:

• Put every agreement in writing. Include a clause that specifies your scope is limited to the specific work you are permitted for, and that pre-existing violations are not your responsibility.
• Photograph the site before you start work. Every room, every ceiling, every wall. This is your evidence if the owner later claims you caused damage that existed before you arrived.
• Pull your own permits under your own license. Never work under someone else's permit unless there is a specific pre-arranged agreement and you understand what you are signing up for.
• Post your permits visibly on the jobsite. NYC requires this and inspectors check.
• Keep insurance certificates current and readily available. If your GL, WC, or disability insurance lapses, your active permits auto-expire, which triggers a cascade of problems.

Quick Reference: Where to Find What

Common Mistakes That Cost New Contractors Money

Every experienced NYC contractor has made at least one of these mistakes in their first year. Learning them from this article is cheaper than learning them from a hearing docket.

Not checking BIS before bidding. You take a job at a building with 12 open violations. Your first day on site, an inspector shows up on an unrelated complaint and finds you. Now you are caught up in the enforcement even though the problems were there before you arrived.

Working on expired permits. You pulled a permit six months ago, the work took longer than expected, and the permit expired. Continuing to work on an expired permit is a separate violation and the fine starts at $2,500. The renewal is $130 per permit.

Not updating your address with DOB. ECB summonses are mailed to the address on file. If you moved your business and did not update DOB, the summons goes to the old address, the hearing date passes without you knowing, and OATH enters a default judgment at the maximum penalty.

Letting insurance lapse. Your GL, WC, or disability insurance lapsed for five days while you switched carriers. DOB NOW automatically expires every active permit in your name, every jobsite you are on now requires new permits to continue, and every job you start during the gap is technically unlicensed work.

Ignoring the pink paper. A hearing notice arrives during a busy month, you stack it on the pile, you forget, the hearing date passes, default judgment entered. Nearly half of NYC contractors default at OATH and most of them did not do it on purpose.

This article is for informational purposes only and does not constitute legal advice. Procedures and database URLs may change. For current information, contact DOB at 311 or visit the official NYC websites. For advice on a specific violation or enforcement matter, consult a qualified attorney.