A combination is only as good as the list of people who know it — and that list almost always grows quietly over time until nobody can say for certain who is on it.
Change it when any of these happen
- Somebody leaves. A departing employee with the combination is the most common reason we are called. Do it on the last day, not next quarter.
- You buy a property with a safe in it. You have no idea who has that number. Assume everyone.
- A bereavement or an estate. Combinations circulate widely at these moments, usually informally.
- A break-in or attempted break-in. Even unsuccessful ones. Assume the number was observed.
- It has been written down. If it exists on a note, in a drawer, or in a phone, treat it as public.
- Nothing has happened for a couple of years. Routine rotation is cheap insurance, and most auditors expect to see it.
Why you should not do it yourself
Mechanical combination locks are changed with a change key inserted through the back of the lock while the door is open and the wheels are aligned on the existing combination. If the key is turned at the wrong point, or the new combination is set incorrectly and the door is then closed, the safe is locked with a combination nobody knows.
That converts a routine visit into a drilling job, a lock replacement, and a considerably larger invoice. It is one of the most common reasons for emergency call-outs, and it is entirely avoidable.
What a proper change involves
- Verifying the current combination opens reliably before anything is touched
- Inspecting the lock and wheel pack while it is accessible
- Setting the new combination with the correct change key
- Testing it repeatedly with the door open — never closing on an untested combination
- Confirming you can operate it yourself before we leave
Choosing a good combination
Avoid dates, addresses and anything sequential. On a mechanical lock, avoid numbers within a few digits of each other, which are harder to dial accurately. On electronic locks, set individual user codes rather than one shared code — that is what makes an audit trail worth having.
And write it down properly
Not on the safe. Not in the drawer beneath it. With your attorney, in a safe deposit box, or in a reputable password manager. The number of safes we drill because the only person who knew the combination died is higher than you would like.
Not sure where you stand?
We have been specifying and servicing this equipment since 1905. A phone call costs nothing.