Should You Change Your Locks After Losing Keys?

Consider what the missing keys could identify

Think through where the keys were last used and what was with them. Keys lost with identification, an address label or belongings linked to your property present a different situation from an unlabelled key misplaced somewhere unknown. You may not be able to establish who has them; the aim is to make a proportionate access decision using the information available.

A spare key lets an authorized person enter, but it does not stop the missing key from operating the same lock. Replacing only the lost key therefore leaves the original access question unresolved. If the circumstances concern you, discuss changing the working key rather than simply adding another copy.

Identify the full set of affected doors

Write down every door the missing key could open. If several doors share that key, looking at the front door alone may leave other entrances unchanged. Also separate mechanical keys from building fobs, garage remotes or other credentials: changing a door lock does not update those separate systems.

• List the entrances and internal doors operated by the missing key.
• Check whether other copies are accounted for and who needs continued access.
• Note whether an authorized person can currently open each affected door.
• Tell the building or access-system manager about any separately managed credential that was also lost.

Rekey sound locks or replace unsuitable hardware

Rekeying compatible locks changes the working key while retaining suitable existing hardware. The old key should no longer operate the cylinders that were rekeyed. Be explicit about the affected doors so the scope of that change is understood.

Replacement may make more sense when hardware is damaged, worn or unsuitable, or when you also want a different lock arrangement. A lost key by itself does not establish that every lock needs new hardware. Use the decision guide to rekeying and replacement to compare access control, condition and compatibility.

Explain access and authorization when you call

Tell Matrix whether you are inside the property, have a spare key or cannot currently enter. Describe the property type, Toronto area and number of affected doors. A request to change key access is different from a request for entry; ask what service can be arranged for your circumstances and what authorization information is needed.

For rented, shared or managed premises, coordinate with the responsible owner or manager before arranging changes. Shared entrances and controlled key systems may involve other people’s access. This is a planning step, not a conclusion about your legal permissions.

Close the loop after access changes

Review the doors covered by the work, test the intended new keys and update your key-holder list. If the missing key later turns up, keep it separate from the new set; it may still open an unaffected door. Avoid labelling spare keys with the full service address.

For household doors, see home lock-change options. A missing work key may affect staff, storage or shared business entrances; our commercial lock-change service and employee access-change guide explain that workflow. Contact Matrix with the doors involved to discuss the next step.