Yes, a tenant can change the locks in NY in most rental situations, but the right is narrower than it sounds. If you live in a building with three or more units, state and city law let you install an additional lock at your own expense without your landlord’s permission, as long as you provide a duplicate key. If you rent a house or a two-family home, your lease controls. And in almost no situation can you simply rip out the landlord’s lock and replace it without consent.
Adding a Lock in a New York City Apartment
If you rent in a New York City multiple dwelling, NYC Administrative Code § 27-2043 gives you the right to install and maintain an additional lock on your apartment door at your own expense. The lock must either work with the building’s master key, or you must give a duplicate key to the landlord or their agent. That choice is effectively the landlord’s: if they require a master-key-compatible lock and you install one that isn’t, you need to hand over a key instead.1New York City Administrative Code. New York City Administrative Code 27-2043 – Locks in Dwelling Unit Doors
This is a statutory right. A lease clause that flatly bans adding a lock does not override it.
Adding a Lock in a Multiple Dwelling Elsewhere in New York
Outside New York City, Multiple Dwelling Law § 51-C grants a nearly identical right. Any tenant of a multiple dwelling can install and maintain a separate lock on their unit’s entrance door, with a few exclusions: public housing operated by a municipal housing authority, hotels, motels, and dormitories. The lock cannot be more than three inches in circumference, and you must supply a duplicate key to the landlord when they request one.2New York State Senate. New York Multiple Dwelling Law 51-C – Rights of Tenants to Install and Maintain Locks in Certain Entrance Doors
One detail that catches tenants off guard: MDL 51-C voids any lease clause that charges extra rent, a fee, or any other charge for the privilege of installing a lock. If your lease says you owe a $50 “lock modification fee,” that provision is unenforceable.2New York State Senate. New York Multiple Dwelling Law 51-C – Rights of Tenants to Install and Maintain Locks in Certain Entrance Doors
Houses and Two-Family Rentals
If you rent a house or an apartment in a building with fewer than three units, neither the NYC Administrative Code provision nor MDL 51-C applies. Those statutes cover multiple dwellings only. For tenants in smaller buildings, the right to change locks depends almost entirely on what your lease says. Most standard residential leases prohibit alterations to the property without the landlord’s written consent, and courts treat lock changes as alterations.
There is one practical opening. If your current lock is broken, your landlord has a duty to maintain the premises in habitable condition, and a nonfunctional lock on an exterior door is a clear habitability problem. Request the repair in writing. If the landlord fails to act within a reasonable time, you may have grounds to make the repair yourself and deduct the cost from rent. Replacing a working lock purely for preference, without lease permission, puts you at risk of a lease violation.
Adding a Lock vs. Replacing the Landlord’s Lock
The statutes protect your right to add a lock. Completely replacing the landlord’s existing lock with your own, so that the landlord’s key no longer works at all, goes further than what the law shields. Without written permission, that kind of swap is where tenants get in trouble.
If you want a true replacement rather than a second lock, ask in writing and get the landlord’s agreement in writing. Otherwise, add a second deadbolt alongside the existing hardware and give them the key.
Giving Your Landlord a Duplicate Key
Both the NYC code and MDL 51-C require you to share access with the landlord. Under the city code, the obligation kicks in automatically as part of exercising your lock-installation right. Under the statewide law, the landlord has to request the duplicate, but you should assume that request is coming.1New York City Administrative Code. New York City Administrative Code 27-2043 – Locks in Dwelling Unit Doors
Neither statute sets a specific deadline, but waiting is a bad idea. Hand over the key the same day you install the lock, or mail it by certified mail immediately so you have proof of delivery. If a pipe bursts or a gas leak develops while the landlord has no way in, you could be held responsible for damage that accumulated because they couldn’t reach it. Document the handoff with a written receipt, a text acknowledgment, or a certified mailing confirmation. If a dispute later reaches housing court, that paper trail is the difference between a straightforward defense and an expensive problem.
Emergencies override everything else. In a fire, flood, or gas leak, the landlord can enter without notice or consent, and if they have the duplicate you provided, they will use it. If you never provided one and the landlord has to call a locksmith during a genuine emergency, expect to be billed for the cost.
What Happens If You Don’t Comply
If a landlord discovers an unauthorized lock change or finds out you never provided a duplicate key, the typical first step is a Notice to Cure. This gives you a set period, commonly ten days, to either hand over the key or restore the original hardware. If you ignore it, the landlord can follow up with a Notice of Termination and then file a holdover proceeding in housing court. The court can treat the unauthorized lock as a material lease breach, which can lead to termination of your tenancy and an award of the landlord’s legal fees.
Being proactive about the duplicate key avoids this entire escalation.
If Your Landlord Changes the Locks on You
The reverse situation matters just as much. A landlord who changes your lock without giving you a key, removes your door, shuts off utilities, or takes any other action to force you out without a court order is committing an illegal lockout.
Under RPAPL § 768, it is unlawful to evict or attempt to evict any occupant who has lived in a dwelling for 30 consecutive days or longer, or who has a lease, except through a court-issued warrant of eviction. The statute specifically lists changing the lock on an entrance door without supplying the occupant with a key as an illegal act.3New York State Senate. New York Real Property Actions and Proceedings Law 768 – Unlawful Eviction
Consequences for a landlord who violates the law include:
- An intentional violation is a Class A misdemeanor, carrying up to one year in jail, with each violation counted as a separate offense.
- Civil penalties of $1,000 to $10,000 per violation, plus up to $100 per day if the landlord fails to restore you to the apartment after you request it.
- Under RPAPL § 853, a tenant removed by force or unlawful means can recover up to three times the actual damages for lost or damaged property, temporary housing costs, and related losses.
New York City mirrors these protections in Administrative Code § 26-521, which uses nearly identical language and applies specifically to city tenants.4New York City Administrative Code. New York City Administrative Code 26-521 – Unlawful Eviction
If you’re locked out, call the police immediately. An officer can sometimes help you regain entry on the spot, and the police report becomes critical evidence if you pursue civil penalties or damages later.
Lock Changes in Domestic Violence Situations
Tenants fleeing domestic violence have additional options. Real Property Law § 227-c allows a tenant who is a victim of domestic violence, or who has a household member who is a victim, to terminate a residential lease early by giving 30 days’ written notice, provided they supply documentation such as an order of protection, a police report, a medical record, or a written verification from a qualified third party. The tenant pays rent only through the termination date and is entitled to a refund of any prepaid rent or deposits covering the period afterward.5New York State Senate. New York Real Property Law 227-C
If you’re staying and just need the lock replaced immediately, the statutory right to add a lock under MDL 51-C or NYC Admin Code § 27-2043 still applies. You install a new lock at your own expense and give the landlord a duplicate. An abuser who is not the landlord has no right to that key. If the abuser is a co-tenant, an order of protection excluding them from the dwelling strips their access rights, and the lock change reinforces that order.2New York State Senate. New York Multiple Dwelling Law 51-C – Rights of Tenants to Install and Maintain Locks in Certain Entrance Doors