Lock Rekeying: Every Reason, Every Property, and the Rekey-or-Replace Decision

What Rekeying Changes, and What It Leaves Alone

Most door locks sold in the United States are built around a pin tumbler cylinder. A brass plug sits inside a housing, and a row of spring-loaded pin stacks keeps it from rotating. Each stack has a key pin on the bottom and a driver pin above it. When the correct key slides in, its cuts raise every key pin until the gap between the two pins lines up with the edge of the plug, a point locksmiths call the shear line, and the plug turns.

Rekeying replaces those key pins with lengths that match a different set of cuts. The old key still slides in, but it now raises the pins to the wrong heights, and the plug stays put. Nothing visible changes. Your knob, lever, deadbolt, strike and finish remain exactly where they were.

That narrow scope is both the strength and the limit of lock rekeying. It answers one question, who can open this door, and it answers it completely: every copy of the old key, including copies you never knew existed, stops working at the same moment. What it doesn't do is change how well the lock resists a kick, a pry bar, picking or bumping, and it won't repair a latch that sticks or a bolt that misses its strike. When someone is disappointed by a rekey, it's usually because they hoped it would solve one of those other problems.

The Situations That Call for a Rekey

Requests for lock rekeying fall into a dozen recognizable situations. Each carries a different level of urgency, and knowing which one you're in helps you decide whether to call tonight or book for next week.

• Buying a home. Sellers, their relatives, agents, cleaners and contractors may all hold copies. Rekey at possession.
• Moving into a rental. Ask the landlord; most leases require permission and a key for management.
• Keys stolen with your address. A wallet, registration or piece of mail traveling with the keys makes this a same-day job.
• Keys lost without identification. A real but lower risk; schedule soon rather than in a panic.
• Tenant turnover. The departing tenant's copies, and any copies they made, leave with them.
• A roommate or partner moving out. Keys go with them, and a spare often stays behind in a drawer somewhere.
• A protective order. California gives tenants a specific right to a lock change within 24 hours of giving the landlord the court order or a qualifying police report.
• An employee leaving, particularly one who left abruptly or never returned keys.
• A break-in. Intruders frequently pocket spare keys and garage remotes on the way out.
• Settling an estate. Caregivers, neighbors and relatives may all have had access over the years.
• Ending a service relationship. Housekeepers, dog walkers, nannies and contractors needed keys; when the arrangement ends, so should the key.
• Nobody knows how many keys exist. That alone is reason enough. A rekey resets the count to the keys in your hand.

Houses, Condos, ADUs and Manufactured Homes

A single-family house in Southern California usually depends on its garage as much as its front door. Count the keyed cylinders and you'll often find a knob and deadbolt at the front, another pair at the back or side, a service door into the garage, an interior door from the garage to the kitchen or laundry room, a keyed handle on a patio slider and a padlock on the side yard gate. People rekey the front and forget the rest, yet the door a former occupant knows best is often the one from the garage.

Condos and townhomes divide the job. The unit door belongs to you; the building entry, pool gate, trash enclosure and parking garage pedestrian door belong to the association and get changed on its schedule. Mailbox compartments can fall on either side of that line, so it pays to ask the manager before booking.

Accessory dwelling units have multiplied across California, and many were keyed alike with the main house for convenience during construction. Once a tenant moves into the backyard unit, that convenience becomes a liability. A round of lock rekeying that splits the keying fixes it neatly: a separate key for each dwelling, and a shared gate cylinder master-pinned so both keys operate it.

Manufactured homes in parks and on private lots often use combination latch-and-deadbolt units sized for thin doors. Some can be rekeyed like any other lock. Others are inexpensive enough, and awkward enough to service, that swapping them for a properly fitted lockset is the better call.

Rental Properties: Turnover, Tenant Requests and California Rules

For landlords, rekeying between tenants is one of the cheapest ways to reduce risk. A prior tenant's key, or a copy they gave a friend, is the simplest possible way into an occupied unit, and the new tenant has no way to know it exists. Many owners make lock rekeying a fixed line on the turnover checklist, right beside paint and cleaning.

California law sets several related expectations. Civil Code section 1941.3 requires landlords to provide working deadbolts on the main swinging entry doors of rental units, along with security devices for windows designed to open. Sections 1941.5 and 1941.6 require a landlord to change the locks within 24 hours of a tenant's written request in certain situations involving a protective order or similar documentation. When the restrained person also lives in the unit, the landlord changes the locks and doesn't give that person a new key.

Just as important is what landlords can't do. Changing locks to push a tenant out, rather than going through the court eviction process, is unlawful in California. That's why we ask about occupancy on every rental rekey.

Tenants who want their unit rekeyed should make the request to the landlord in writing. Most leases require approval and a copy of the new key, and a reasonable landlord will usually agree, especially if the tenant offers to pay for it.

Businesses: Staff Changes, Master Keys and Restricted Keyways

Commercial rekeying is mostly about turnover. Managers leave, shift leads change, cleaning contracts end, and every departure raises the same question: how many copies of the key walked out with that person, and how many were made along the way?

Storefronts typically use aluminum doors with a narrow-stile deadlock operated by a threaded mortise cylinder, plus a steel rear door with a rim cylinder on the exit device. Offices add lever locks with standard or interchangeable cores, file cabinets with cam locks, and server or supply closets. Warehouses add padlocks on roll-up doors and yard gates. Complete commercial lock rekeying reaches all of it.

Master keying changes the math. In a master system, each cylinder accepts two or more keys: a change key for that door and a master that opens a group of doors. When one change key goes missing, only the doors it opened need new pins. When a master goes missing, every cylinder beneath it is exposed and the job grows accordingly.

Restricted keyways attack the copying problem directly. Their blanks aren't sold at hardware stores or kiosks, and authorized copies require a signature or card from the account holder. A 'Do Not Duplicate' stamp on an ordinary key is a polite request; a restricted keyway is an actual barrier. For businesses that rekey often, switching to one can stretch the time between rekeys considerably.

Rekey or Replace: A Door-by-Door Decision Guide

The best outcome is rarely all one or all the other. Judge each lock on its own merits using a few practical tests.

Rekey when: - The key turns smoothly without lifting, jiggling or pressing. - The latch catches the strike every time, and the deadbolt throws fully without anyone pushing on the door. - The lock is a reasonable grade for its door, such as an ANSI/BHMA Grade 1 or 2 deadbolt on a main entry. - You like how it looks, and it does what you need.

Replace when: - The plug wobbles, the key binds or the lock only cooperates at certain angles. - The lock was forced, bent or pried during a past break-in. - A main entry relies on a light-duty deadbolt or a keyed knob alone. - You want a different function: keypad or smart entry, levers for easier grip, or a high-security cylinder. - The brand is obscure, parts are unavailable, or the cylinder was never designed to be serviced.

Consider a middle path when: - The lockset is sound but its cylinder is worn; a new cylinder alone may do. - Mixed brands block a one-key goal; converting or replacing a single lock may let the rest be re-pinned. - Budget is tight; rekey everything now and replace the weakest deadbolt later.

Price alone shouldn't decide it. Rekeying a lock that will fail next year means paying twice, and replacing solid hardware only to get new keys throws good metal in the trash.

When Lock Rekeying Isn't Possible or Isn't Enough

Some locks can't be rekeyed in any practical sense. Inexpensive padlocks and some imported locksets have cylinders that are crimped or staked shut, and opening them destroys the housing. Many sliding-door handles and older garage T-handle locks use simple wafer mechanisms that cost less to replace than to service. Disc-detainer locks and certain high-security designs can be reconfigured only with factory parts or through an authorized dealer.

Kwikset SmartKey cylinders deserve their own note. They reset in seconds with a learn tool when you have the working key, but without one they need disassembly or a replacement cylinder. Early SmartKey versions also drew criticism for a forced-rotation weakness that later designs addressed, so if an older one guards your main door, replacing it is worth considering.

Rekeying also falls short when the real risk is physical. If a door was kicked in, the weak point was probably the frame: a soft jamb, a strike held by short screws, or a gap that let the bolt slip free. The fix there is reinforcement, and the rekey is only part of the job. Likewise, if keys were never the concern and you simply want stronger locks, a high-security cylinder or a heavier deadbolt is where the money belongs.

The Electronic Half: Smart Locks, Keypads, Remotes and Fobs

A modern property often carries as many electronic credentials as metal keys. After a purchase, a breakup or a staff change, they deserve the same attention as the cylinders during any lock rekeying.

• Keypad and smart deadbolts. Delete old user codes, change the programming or master code, and remove former users from the app. If you bought the house, factory reset the lock and enroll it in your own account.
• Backup cylinders. Most keyed smart locks still have one, and its key may have been copied freely. It rekeys like any other cylinder.
• Retrofit smart locks. Models such as August replace only the interior thumbturn, so the exterior cylinder is still your original deadbolt and needs rekeying on its own.
• Garage openers. Holding the learn button on most residential openers erases every paired remote. Re-pair the remotes you're keeping, change the keypad code, and clear the built-in garage buttons in any car that has left the household.
• Gate transmitters and building fobs. These are usually controlled by an HOA or property manager, who can deactivate a lost one without touching a single lock.

Commercial access control, with card readers, electric strikes and request-to-exit sensors, is its own category. Some changes are simple credential edits in software; others involve low-voltage wiring that may call for a licensed low-voltage contractor. We'll tell you which side of that line your system sits on.

Vehicles, RVs and Other Locks People Ask About

Car owners sometimes ask about rekeying after losing a key. Mechanically, many vehicle door and ignition cylinders can be re-wafered to a new key, but on a modern car that's rarely the point. The engine is protected by an immobilizer that recognizes the transponder chip or smart fob, so the important step after a loss is erasing the missing key from the car's memory and programming the keys you keep. Some makes and models allow that on site; others require dealer-only programming.

RVs and trailers are a different story. Many compartment locks across manufacturers share a small number of key codes, so a stranger carrying a common RV key may open your storage bays. Replacing those cam locks with unique-keyed versions, and rekeying the entry door where its design allows, gives a seasonal vehicle genuine protection.

Other frequent requests include desk and cabinet cam locks, tool chests, gun cabinets and file cabinets. Many use wafer or pin mechanisms that can be set to a new code or replaced with a rekeyable version. Safes are their own specialty, handled through combination changes and lock replacements rather than rekeying in the usual sense, and some locked safes can only be opened by drilling.

What Shapes the Price

We don't publish flat prices for lock rekeying, because the same request can mean very different work from one property to the next. These are the things that move the number:

• How many cylinders, counted individually, including padlocks and mailbox locks.
• Brand and keyway. Common residential cylinders are quick, while high-security systems need controlled parts.
• Condition. Dirty, corroded or seized cylinders need cleaning and new springs.
• Whether a working key exists, since picking or decoding adds labor.
• Master keying or restricted keyways, which require more pins, planning and records.
• How many keys you want cut, and whether they're restricted blanks.
• Any replacements, strike reinforcement or extra hardware you ask for.

You hear the quote before work begins. If something changes once a lock is open, such as a cracked plug or a seized pin stack, we stop, explain what we found and get your approval before going further.

Verification, Licensing and What to Have Ready

Every rekey starts with confirming that the person asking has the right to ask. That protects owners from a former partner, tenant or employee who might try to have locks changed against them.

Have these ready: - Photo ID. - Proof tied to the property: a deed, closing statement, utility bill, lease with landlord approval, or management agreement. - For estates, the court-issued letters or trust documents naming you; for agents, the power of attorney. - For businesses, authority from the owner or an officer, plus landlord approval if your lease reserves lock changes to the landlord.

Julian's Locksmith operates under California locksmith company license LCO7891, issued by the Bureau of Security and Investigative Services under the Locksmith Act, Business and Professions Code section 6980 and following. Anyone can look up a license at search.dca.ca.gov, and it's worth doing for any locksmith you let near your locks.

Where We Work and When

Julian's Locksmith is a mobile service based in the University Heights area of San Bernardino, near Cal State San Bernardino. We bring pins, cylinders, a key machine and hardware to the property, so lock rekeying happens at your door rather than at a counter. The service area covers the Inland Empire, the San Gabriel Valley and the Pomona Valley, along with north Orange County and southeast Los Angeles County.

Hours are 6:30 a.m. to 11:30 p.m., seven days a week. We're closed overnight, and we aren't a 24/7 operation. If keys are stolen after we've closed, take the interim steps you can: erase garage remotes, secure doors from inside with the deadbolt thumbturn and a door bar or wedge, stay with family if you feel unsafe, and call when we open. When you reach us at (951) 903-3193, we'll give you an honest arrival estimate based on where you are and what else is on the schedule.

Holding On to Key Control After the Rekey

Lock rekeying resets the count. Keeping it there is a matter of a few habits that cost almost nothing.

• Decide how many keys should exist, write the number down, and note who holds each one.
• Number business keys and log them at hire and at departure, with a signature both times.
• Keep spares with a trusted person, not under a mat, in a fake rock or on top of the door frame.
• Leave names and addresses off key tags.
• For rentals, record which cylinder or key code is installed in each unit, and update it at every turnover.
• Review electronic access whenever you review keys, so codes and remotes don't drift out of sync with the metal.
• Treat a missing key as information, not just an inconvenience: ask where it was last seen and what else was with it.

With those habits in place, the next rekey becomes a decision you make on your own schedule instead of a reaction to something that already went wrong.