To report an illegal apartment in Suffolk County, contact the code enforcement or building department of the town or incorporated village where the property is located. Suffolk County itself does not handle these complaints. Each of the ten towns and the dozens of incorporated villages inside them runs its own enforcement office, with its own phone line and online complaint form.
Finding the Right Town or Village
Jurisdiction is the first thing to get right. A house in Deer Park is handled by the Town of Babylon. A house in Commack goes to the Town of Smithtown. File with the wrong office and your complaint waits in a queue that belongs to someone else.
If you’re unsure which municipality covers an address, check a property tax bill for that location or use the Suffolk County tax map viewer. Also check whether the address sits inside an incorporated village such as Patchogue, Amityville, or Lindenhurst; if it does, the village handles code enforcement, not the surrounding town.
For the five largest towns:
- Brookhaven: Call 631-451-8696 or contact the Building Division through the town website.1Town of Brookhaven. Illegal Housing
- Islip: Call the Division of Code Enforcement at (631) 224-5460 or file through the Constituent Services online form.2Town of Islip. Constituent Services
- Huntington: Use the illegal housing form on the town website, or call the 24-hour hotline at (631) 351-3234.3Town of Huntington. Division of Code Enforcement
- Babylon: Dial 3-1-1 (or 631-957-7474 from outside the town) or use the online Report a Concern form. Urgent after-hours concerns go to the Department of Public Safety at (631) 422-7600.4Town of Babylon. 3-1-1 / Report a Concern
- Smithtown: File through the Building Department Complaint Form on the town website.5Town of Smithtown. Building Department Complaint Form
What to Put in the Complaint
Start with an exact street address. Inspectors cannot act on “a house somewhere on Oak Street.” Then say where on the property the suspected unit is: “the basement apartment with a separate entrance on the east side” gives an inspector something to look for. The Town of Babylon specifically asks complainants to include the number of tenants and the location of the apartment’s entrance.6Town of Babylon. Frequently Asked Questions – Landlord/Tenant Issues
Describe what you have actually seen. Useful observations include:
- Separate mailboxes or doorbells at a home zoned for a single family
- Extra utility meters that don’t match the property type
- People routinely using a basement or side door as an independent entrance
- Windows boarded up, missing, or too small to climb through in an emergency
- Extension cords running between structures or other makeshift electrical setups
You do not need to prove anything is illegal. That is the inspector’s job. Your job is to give them enough detail to know what to look at when they arrive.
How to Submit and Whether You Can Stay Anonymous
Most towns accept complaints by phone during business hours and through an online form at any time. Phone lets you describe the situation in your own words. Online creates a written record automatically.
Anonymity policies vary. Some online forms require your name and contact information so inspectors can follow up for clarification; others let you skip those fields. Even where towns ask for your identity, they generally keep complainant information out of public records. If anonymity is important to you, call the town clerk’s office and ask about their policy before you file.
If the situation is an immediate danger to life — a gas leak, exposed live wiring, someone trapped in a unit with no way out — call 911 instead. Code enforcement works on business-day timelines. Emergency responders do not.
What Happens After You File
The town logs the complaint and typically assigns a case or reference number. A code enforcement officer or building inspector is then assigned to investigate, usually starting with a site visit. They will look for construction done without permits, rooms that fail minimum safety standards, and occupancy that doesn’t match the property’s certificate of occupancy.
New York’s Multiple Residence Law requires any dwelling converted into a multiple-unit residence to have a certificate of occupancy reflecting that use.7New York State Senate. New York Multiple Residence Law 302 – Certificate of Occupancy A single-family home rented as two households almost certainly lacks one, and that alone is a violation.
How fast an inspector visits depends on caseload and the apparent urgency. A complaint describing visible safety hazards moves faster than one about extra cars in the driveway. Most towns treat complaints as one-way submissions rather than open cases you can track, so don’t expect regular status updates. If weeks go by with no visible activity, call the department, reference your case number, and ask.
When an inspector confirms a violation, the town issues a written order to the property owner setting out what needs to be corrected. At that point the matter becomes a legal proceeding between the municipality and the owner. You are not a party to it and will not control the outcome.
What the Property Owner Faces
Under New York’s Uniform Fire Prevention and Building Code, an owner who receives a written order and fails to comply can be fined up to $1,000 per day the violation continues, with jail of up to one year also on the table. If an illegal alteration blocks someone’s ability to escape during a fire, the owner faces a separate misdemeanor charge, and a court can order the illegal construction removed or the building vacated.8New York State Senate. New York Executive Law 382 – Remedies Individual towns may add their own penalties by local ordinance. Ignoring a violation order gets more expensive every month.
If You Live in the Apartment Yourself
Sometimes the person reading this isn’t a neighbor. It’s a tenant who just realized their own unit might be illegal. Reporting could eventually trigger a vacate order that displaces you, and that changes the calculation. Two rules matter most.
Retaliation Is Prohibited
New York law prohibits landlords from evicting or punishing a tenant for filing a good-faith complaint about housing code violations with a government agency. If your landlord tries to evict you, refuses to renew your lease, or sharply raises your rent within one year after you complain, the law presumes the action is retaliatory and the landlord has to prove otherwise in court.9New York State Senate. New York Real Property Law 223-B – Retaliation by Landlord Against Tenant The protection covers complaints made to code enforcement, the fire marshal, or any government authority handling health or safety, including complaints filed on your behalf by a legal aid organization.
Vacate Orders Are Not Evictions
If a town determines the unit is unsafe, it can order everyone out. A vacate order from code enforcement is not the same as a landlord-initiated eviction and doesn’t create the same record, but it does mean finding somewhere else to live, sometimes on short notice. The landlord cannot legally re-rent the space until the violations are corrected and a proper certificate of occupancy is issued.7New York State Senate. New York Multiple Residence Law 302 – Certificate of Occupancy
Rent and lease enforceability in an illegal unit also comes into play if a nonpayment case ever reaches housing court; a landlord generally cannot collect rent on space not legally authorized for residential use, though there are exceptions and the doctrine has limits.10New York State Unified Court System. Illegal Apartment Before you stop paying rent, withhold anything, or file a complaint about your own unit, talk to Legal Services of Long Island or another legal aid provider that serves Suffolk County. The specifics of your lease and your situation matter, and this is not a decision to make on your own.