Rekeying vs. Changing Locks: Which Do You Need?

A lock has two main components that matter here: the hardware you see (the knob, handle, deadbolt, or mortise lock body) and the tiny internal pins that determine which key operates it. When you rekey a lock, a skilled locksmith disassembles the cylinder and replaces those internal pins so that the old key no longer works — only the new key does. The lock hardware itself stays exactly where it is. When you change a lock, the entire lock unit is removed and a new one is installed in its place.

Think of it this way: rekeying changes the 'combination' inside an existing lock, while replacing it swaps out the whole mechanism. Both results are the same from a security standpoint — your old key becomes useless — but the path to get there, and the factors that affect your final quote, are very different. A professional can often rekey multiple locks in a home and key them all to one master key in a single visit, which is especially useful for properties along busy corridors like Klockner Road or in established neighborhoods like Hamilton Square.

Rekeying makes the most sense when your existing lock hardware is in good working condition and you simply need to control who has access. Classic situations include moving into a newly purchased home (yes, do you need to rekey a new lock? — absolutely, because builders, prior owners, and real estate agents may all hold copies of the original key), ending a lease or a relationship, losing a key set, or after any situation where keys were out of your possession for an unknown period of time. For rental property owners near Nottingham or the Yardville area of Hamilton Township, rekeying between tenants is standard practice and far less disruptive than full hardware replacement.

Rekeying is also the go-to solution when you want to consolidate. If your front door, back door, and side gate all use different keys, an experienced locksmith can rekey all of them to operate on one single key — a process called master keying. It's a practical upgrade that requires zero new hardware. If you're wondering how do you rekey a door lock yourself, the short answer is: it requires a specialized follower tool, a plug follower, and a pinning kit matched to your specific lock brand — tools most homeowners don't own. For a mortise lock especially, the cylinder removal process can be tricky without experience, and an incorrect reassembly can leave you locked out or with a binding lock. Calling a trained locksmith is the reliable route.

There are clear situations where rekeying simply isn't enough — or isn't possible. If your lock hardware is visibly damaged, corroded, or has a worn cylinder that binds or sticks, rekeying the internals won't fix the underlying mechanical problem. The same goes for a door knob lock or deadbolt that was forced, drilled, or tampered with — the hardware integrity is compromised and should be replaced entirely. In these cases, our team restores your entry door to proper working order with a full lock replacement, keeping your home protected rather than patched.

Upgrading your security grade is another strong reason to replace. If your home currently has basic builder-grade knobs, moving to a high-security deadbolt or a quality mortise lock is a meaningful improvement — and that requires new hardware. Mortise locks, which are recessed into the door edge rather than surface-mounted, offer superior strength and are common in older Hamilton Township homes and commercial properties. A skilled locksmith will assess your door prep (the existing cutout) and recommend a compatible replacement that fits your door without requiring major carpentry work. If your door frame or strike plate was damaged during a break-in attempt, we also handle emergency door repair as part of a complete security restoration — because a strong lock on a compromised frame offers little real protection.

One detail that trips up DIY lock projects is fitting. If you're replacing a mortise lock, the body dimensions must match your door's existing mortise pocket precisely. A key measurement here is the backset — the distance from the edge of the door to the center of the keyhole. For a standard cylindrical lock it's typically 2-3/8 or 2-3/4 inches, but if you're asking how do you measure a backset on a mortise lock, the process is slightly different: you measure from the door's face edge to the center of the spindle hole on the mortise case, and the case depth must also fit within your door's thickness. Getting this wrong means the lock won't install correctly. Our team arrives with the right gauges and a selection of hardware to ensure a precise fit on the first visit.

Smart locks and keypad deadbolts add another layer of consideration. Homeowners who want to know how do you change the code on a door lock — or how do you change a combination lock code on a keypad unit — will find that most modern electronic locks allow code changes through a simple button sequence outlined in the manufacturer's instructions, no locksmith needed for that step alone. However, if you're installing a new smart lock or rekeying a traditional lock to work alongside a keypad entry, a professional installation ensures proper alignment, correct backset fit, and reliable operation. For commercial properties requiring keypad or access-controlled mortise lock systems, our commercial locksmith services cover full installation and programming.

A question we hear often is: how do you know you can trust a locksmith? Legitimate locksmiths — like our team at Hamilton Township Locksmith — will always ask for proof of ownership or residency before performing any work. That means a photo ID, a utility bill, a lease agreement, or a vehicle registration. This isn't bureaucratic inconvenience; it's how a responsible locksmith protects you and your community. Be cautious of any technician who begins work without asking. Our team is insured, and every job starts with an identity and ownership check, no exceptions.

On the topic of cost: how much does a locksmith cost in NJ? There's no single honest answer, because the final price depends on several real factors — the type of lock or vehicle involved, the complexity of the service (rekeying one cylinder vs. installing a new mortise lock system), your location and travel distance, the time of day (overnight emergency calls carry different logistics), and the parts required. What we commit to is confirming an exact, up-front price before any work begins, so there are no surprises on your bill. If you're in the middle of a lockout on Whitehorse-Mercerville Road at 2 a.m. or need a commercial locksmith for a multi-unit property rekeying, call us at (609) 507-2749 — we're available around the clock and will walk you through your options before a single tool comes out of the bag.

It's also worth answering a common concern directly: what locks can locksmiths not open, and can a locksmith open any lock? A trained locksmith can open the vast majority of residential and commercial locks through legitimate, non-destructive methods — picking, decoding, or using bypass tools specific to the lock type. High-security locks with anti-pick pins and reinforced cylinders, biometric safes, and certain high-grade commercial access systems may require destructive entry or specialized decoding tools beyond standard field equipment. In practice, for everyday residential and automotive lockouts, an experienced locksmith will have the right tools for the job. What a reputable locksmith will never do is help someone gain access to a property they cannot verify ownership of — full stop.

Our mobile locksmith team serves all of Hamilton Township, NJ — from the older craftsman homes near Greenwood Avenue to commercial strips along Route 33, apartment complexes near the Hamilton train station, and everything in between. Whether you need a single door knob lock rekeyed, a full mortise lock system installed in a rental property, an emergency locksmith response after a break-in, or help getting back into your car in a Mercer Mall parking lot, we show up equipped and ready. Here is a full picture of what we handle: residential lock rekeying, residential lock replacement, mortise lock installation and repair, deadbolt installation, door knob lock replacement, smart lock installation, keypad lock installation and programming, master key system setup, emergency lockout service (home), emergency lockout service (car), emergency lockout service (business), emergency door repair, door frame and strike plate repair, high-security lock upgrades, lock hardware consultation, commercial lock rekeying, commercial deadbolt installation, commercial mortise lock service, access control system installation, mailbox lock replacement, garage door lock service, padlock opening and replacement, safe opening, safe lock repair, automotive key cutting, car key programming, transponder key replacement, ignition lock cylinder service, and broken key extraction. No matter the job, every service starts with a confirmed quote and ends with a working lock.