What problem is the reader trying to solve: key control, damaged/incompatible hardware, a desired feature, or a separate door/frame concern?
Start with the problem you want solved
List the outcome you need before comparing scopes: change key access, address a hardware problem, choose a different function, or have a door/frame concern assessed. Those goals can overlap, but they are not interchangeable. A replacement may change hardware while leaving a door/frame concern unresolved; a rekey is not a promise to repair hardware or the door.
What lock, keyway, door preparation and hardware information should a qualified provider verify before quoting either option?
What must be checked for your lock and door?
Before a provider quotes either option, ask them to identify the lock brand and model, cylinder or keyway compatibility, the door’s existing preparation, and the hardware’s present operation. Ask what they have actually verified and what remains unknown. A symptom alone does not establish whether the lock, its fit, or another part of the door is the issue.
Rekey compatibility depends on the specific lock design. Kwikset’s SmartKey is an example limited to its own SmartKey products: Kwikset says the prior key will no longer operate after its product is rekeyed, and its normal method requires the current working key. That example does not show that an unidentified lock can be rekeyed, and this guide does not provide the procedure. If the working key is missing, ask the manufacturer or a qualified provider what options apply to the identified lock.
What does each option change and leave unchanged about existing keys, hardware condition, door security and access records?
What changes—and what does not?
For a compatible lock, a rekey changes key control while retaining the existing hardware. It does not, by itself, establish that the hardware is in good condition, correct an installation or door/frame concern, add a feature, or establish a security level.
Replacing changes the hardware and may be considered for a condition, fit, or feature reason. It does not automatically resolve a separate door/frame issue or establish a security improvement. Ask the provider to state exactly what hardware will be removed and installed, and what existing parts or conditions are outside that work.
Neither a physical rekey nor a lock replacement should be assumed to remove electronic credentials, codes, app access, or other non-key access. Ask separately which access methods exist and which, if any, are included in the written scope. Keep a record of the keys or access methods you expect to work afterward, who is authorized to hold them, and any unresolved access that needs separate follow-up; do not treat a service description as proof that every prior user has lost access.
What written scope, parts, labor, compatibility, warranty and key-control details should be compared?
Compare written scopes, not just the service label
Ask for each option to be described in writing for the identified lock and door. Compare:
- the exact work proposed and what the provider verified about model/keyway compatibility and door preparation;
- whether existing hardware remains, or which parts are removed and replaced;
- parts and labor included, plus any work explicitly outside the scope;
- how the proposed work addresses your key-control goal, including what keys are expected to operate afterward and what access is not covered;
- the warranty terms and who handles a compatibility or workmanship concern; and
- the total and any possible added work, with your approval process before scope changes.
These are questions to clarify competing proposals, not a standard price list or a guarantee of a particular result. If two quotes use different assumptions about compatibility, hardware, or access control, ask each provider to make those differences explicit before comparing totals.
When do ownership, rental, fire-egress or jurisdiction-specific requirements need verification before changing hardware?
Check authority and egress before changing hardware
If you rent, share ownership, manage the property, or are unsure who may authorize the change, verify the approval and access-record process with the responsible owner or property manager before work. If the door is part of a required exit route, or local requirements may apply, ask the responsible building authority or a qualified local professional to verify the applicable requirements for that door and hardware. This guide does not determine legal rights, code compliance, or fire-egress suitability.
For an urgent access or safety concern, seek appropriate local help. Do not use this comparison as instructions for opening, bypassing, disassembling, drilling, or adjusting a lock.