Start with who controls the door, then decide whether outstanding keys are an acceptable risk. If you own the home or you have written approval from the owner or manager, rekeying sound hardware is the usual way to make a departed roommate’s key stop working. If you rent, the lease usually comes first. You cannot assume every leftover copy was returned. A key in hand does not prove no duplicate exists.
Swift Key San Diego is a referral service. Independent licensed locksmiths perform work only after you have authority to change that lock. They set the price and the schedule.
Who has authority, and what you cannot know about copies
Not every roommate departure is yours to fix at the cylinder.
Owners and deed holders can usually rekey doors they control, after confirming no co-owner or remaining occupant has a right to that key.
Renters generally need landlord or manager permission. Most leases treat lock changes as an alteration. Ask in writing. If the roommate is still a named co-tenant, excluding them with a new key can be a lease or occupancy dispute, not only a hardware job. The tenant rekey rights in California guide starts with the lease and separately explains Civil Code 1941.5 and 1941.6 for qualifying abuse-or-violence cases. Those statutes are not a general roommate-turnover rule.
Unknown copies. People make extras. Parents hold spares. Partners keep a copy. If you cannot account for every key that ever existed, assume one might still work until the pins change.
When a rekey may be unnecessary. The roommate left on good terms, you hold every known copy, and you still trust that accounting. That is a judgment call, not a requirement to leave the old keying in place.
What rekeying actually involves
A locksmith removes the cylinder, rearranges the pins, and cuts new keys. The finish and body stay if the lock is sound. Old keys stop working.
If you have more than one compatible exterior lock, ask about keyed-alike pinning so one new key opens the doors that share a keyway. Mixed brands usually cannot share a key without replacing some hardware. For that comparison, see rekey vs. new locks and lock replacement.
Ask the locksmith for an itemized quote: each cylinder, extra keys, and any lock that must be replaced instead of rekeyed. Swift Key does not set a per-cylinder fee.
The rental permission question
If you rent, get written approval before anyone rekeys. Explain that a roommate moved out and you want the unit’s keys limited to remaining authorized occupants. Keep the reply.
If you own the unit, you still need to respect any HOA or building lock rules on shared doors.
The access points most people forget
A front-door rekey does not reset everything.
Garage codes. Change keypad codes the roommate knew. This is usually an opener-menu task.
Gate fobs and building cards. Ask the HOA or property manager to deactivate credentials. Timing is their process, not a locksmith visit.
Mailbox key. Shared mail access may continue until the box is changed. For USPS cluster boxes, start with the post office. A locksmith may help only with a private mailbox you control.
Hidden spares. Move or remove any spare the roommate knew about.
Alarm codes. Delete their user code.
Wi-Fi password. Change it if they should no longer use the network.
The smart lock alternative (when it applies)
If a smart lock is already installed and you control the admin account, deleting their code can retire their keypad access. It does not retire a mechanical key they still hold, unless you also rekey or disable that cylinder.
A new smart lock installation is optional, not required, for a roommate departure. Compare hardware in smart lock vs. deadbolt.
Quote checklist (no published prices)
Before work starts, the independent locksmith should confirm:
- Authorization (owner, manager letter, or other proof they accept)
- Cylinder count and brand mix
- Whether keyed-alike is possible
- Opening or lockout work, if you are locked out
- Their total, in writing
Availability is theirs to state. Swift Key does not promise weekday, evening, or weekend arrival.
Frequently asked questions
Should I change the locks when a roommate moves out?
Rekey if you have authority and you cannot account for copies. Replace only if the hardware is failing or you want different locks. If you rent, get written approval first. If a co-tenant still has occupancy rights, get legal advice before excluding them.
How much does it cost to rekey after a roommate leaves?
The locksmith sets the price from the cylinder list. Ask for an itemized total. See lock rekey.
Can I rekey a rental myself?
The lease may forbid it. Even when allowed, pinning a cylinder is easy to get wrong. Get written approval, then decide whether you or a locksmith will do the work.
What if my roommate still has a fob or building access card?
Contact the HOA or manager. A door rekey does not deactivate building credentials.
Do I need to do anything about the garage if a roommate moves out?
Yes, if they knew a keypad code or still have a remote. Change the code or reprogram remotes per the opener instructions.
How quickly can a locksmith come out in San Diego?
The matched locksmith confirms timing. Call Swift Key San Diego at (858) 400-4082 for a referral.
Roommate just moved out and you already have authority to change the lock? Call (858) 400-4082. Swift Key refers independent licensed locksmiths in San Diego County. They confirm hardware, authorization, and price.