Plan to rekey or change your locks after a partner, ex, or roommate leaves, even if they returned their key. A returned key shows that one key came back, not that no copies exist. So the real question is whether you can be sure who still has access. Once every key, code, and shared entry is listed, you decide between rekeying and replacing, and when to do it.
List every way the person could get in
Start with an inventory, not a lock. Walk the home and note each route the departing person had, including the ones they rarely used.
- Front door keys, including a deadbolt that takes its own key
- Back, side, or balcony doors
- Mailbox, storage, bike room, or basement keys
- Keypad codes and smart lock app accounts
- Building entry fobs, cards, and intercom codes
- Spares held by friends, family, neighbors, a dog walker, or hidden outside
Then confirm who has the say over the locks. If you rent, share a lease, or co-own the home, settle that with your landlord or the others on the paperwork before booking anything. If the worry is about your safety rather than keys, reach out to people who handle that kind of situation as well.
Rekey or replace, and when to do it
What tips the choice
Rekeying leaves the lock on the door and changes the pins inside the cylinder, the part the key slides into, so old keys no longer turn it. It suits hardware that works well: the key turns smoothly, the latch catches, nothing wobbles. Replacing makes more sense when the lock is worn, sticky, or loose, or when the lock itself is part of the worry, such as a key any hardware store can copy.
Codes can go one at a time
Many keypad and smart locks hold a separate code or account for each user, so deleting one person's access leaves everyone else's alone. A keyed lock has no such option. An old key works until the lock is rekeyed or replaced.
Picking the moment
Changing locks before the move-out can leave someone's belongings behind a door they can't open. Waiting weeks leaves old keys working. Tying the change to the handover avoids both: belongings out, keys returned, locks changed right after. Whatever you choose, the people staying need new keys in hand before the old ones stop working.
When the building holds some of the keys
In an apartment building you usually control your own door and little else. The main entry, intercom, fob readers, and often the mailboxes belong to the landlord or property manager. Rekeying your unit does nothing about a fob still in the departing person's pocket.
Ask whoever manages the building to deactivate that person's fob or card, change any shared entry code they knew, update the intercom listing, and confirm who holds storage and mail keys. Property managers handling a resident's move-out can work from the same list.
What to hand over before the work and on the day
Turn the inventory into a short note for the locksmith and the people staying.
- Which doors are changing, and whether they should share one key
- How many keys each remaining person needs
- Who holds the spare, and where it lives
- Which codes, accounts, and fobs to retire, and who is handling each
- Anything you've noticed about the door, like a sticky key or a loose handle
On the day, try each new key in every lock it should open while the door is still open, then confirm an old key no longer turns. To plan a rekey or lock change in Bedford-Stuyvesant, Crown Heights, Clinton Hill, or elsewhere in Brooklyn, call Nostrand Locksmith at (516) 644-8976.
Frequently asked questions
If my ex or roommate gave back their key, can I be sure there is no copy?
No. Copying a house key leaves no mark on the original, so a returned key cannot tell you whether a spare was cut, lent out, or left in a car. Rekeying or replacing the lock makes every earlier key useless, including copies the person may have handed to someone else.
Is it better to change the locks before or after the person moves out?
Changing the locks right after the handover avoids most of the trouble. If the person still needs to collect belongings later, set a time when someone is home to let them in, rather than leaving an old key working until then. Either way, the people staying should have their new keys before the change takes effect.
Do I need to change a lock I share with a roommate who is staying?
A shared lock needs changing if the person leaving had a key to it, because any old key still opens it. The roommate who stays simply gets a new key. If several doors in the home run on one key, rekey them together so the household still carries a single key.
What should I do about a keypad code or smart lock access the other person knew?
Delete that person's code or user account and change any shared code they knew. Check the lock's app for admin users too, since an admin can create new codes. If the keypad lock also has a key cylinder for backup, that cylinder needs the same rekey or replace decision as any keyed lock.