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HMS Locksmith is an Allston-based locksmith that does rekeying, lock changes and master key work for landlords and management companies across Boston, Chelsea, Cambridge, Quincy and the surrounding cities. The days between one lease and the next are always crowded, and the lock work tends to get squeezed between the painters, the cleaners and the next tenant’s move-in date.
That is a mistake worth avoiding. Rental turnover locks are one of the few things in a unit that directly affect the next tenant’s safety on night one. This guide lays out a simple routine you can repeat every time a unit changes hands, plus the Massachusetts rules that set the baseline.
The baseline: what Massachusetts requires
The Massachusetts State Sanitary Code, Chapter II (105 CMR 410), sets minimum housing standards, and it has a section on locks. In plain terms, the owner must provide and maintain locks so that every dwelling unit and every unit entry door can be secured against unlawful entry, and openable exterior windows can be secured too. Larger buildings must also have a main entry door that closes and locks on its own. The code also requires that locking devices not trap people inside the building.
The City of Boston’s housing code guidance for owners says the same thing in everyday language: buildings and units must have locks on the doors, windows that open to the outside must have locks, and locks must not trap anyone inside. If you are unsure how the rules apply to a specific building, Boston’s Inspectional Services Department is the place to ask.
Notice what the code does not say. It sets a standard for working locks, not a rule that you must rekey between every tenant. That decision is yours, and it is a good one to make the same way every time.
The City of Boston summarizes these rules on its Inspectional Services housing code page, including who to call if something is not up to code.
Why rekey between tenants
Departing tenants hand back keys, but you have no idea how many copies were cut. Keys get lent to partners, dog walkers and friends who watered the plants. Rekeying makes every one of those copies useless.
As our rekey and master key page explains, rekeying means removing the cylinder, changing the pins to match a new key pattern and reassembling the lock. It is an inexpensive alternative to changing the locks, and if a key is lost or stolen you will want to block access from that key as soon as possible. If the existing locks are in good condition, a tenant change does not have to mean replacing the hardware.
A turnover routine you can repeat
Use the same checklist on every unit so nothing gets skipped when the schedule is tight.
1. Collect and count keys at move-out
Write down how many keys you handed over at move-in and how many come back. Include mailbox, storage, laundry room and bike room keys. A shortfall is a reason to rekey the affected lock, not a reason to wait.
2. Rekey the unit entry door
Rekey the knob or lever and the deadbolt to the same new key. If either lock sticks, is corroded or no longer latches cleanly, replace it now rather than after the new tenant calls.
3. Check secondary doors and windows
Rear doors, porch doors and basement doors are easy to miss. Test every openable window lock, since the sanitary code covers those too.
4. Test common doors
Make sure the main entry door closes and latches on its own, and that shared exterior doors lock properly. A door closer that has drifted out of adjustment is a common reason a building door stops latching.
5. Deal with the mailbox
In apartment buildings, the property owner or manager is generally responsible for the tenant mailbox locks, while the post office controls the master door. Plan for the mailbox lock at turnover just like the unit door. HMS handles mailbox lock changes and will ask the person requesting the work for official ID and proof of address.
6. Record and cut new keys
Log the new key code, the date and how many keys went to the incoming tenant. Keep your own copy labeled and stored securely.
Master keys for multi-unit owners
If you own several units or buildings, a master key system can save a lot of time. Each unit keeps its own key, but a master key opens them all, so you carry one key instead of dozens. Access can be tiered so a maintenance person gets some doors and a manager gets more, often without replacing locks. Key control systems help track duplicates, especially of the grand master key.
The trade-off is responsibility. A lost master key is a serious problem, so keep a short list of who holds one and treat it like cash.
A note on tenant lock changes
Sometimes it is the tenant, not the landlord, who calls a locksmith. A bill now moving through the Massachusetts House, H.1562, would require a locksmith hired to change locks on a rental property to make a good faith effort to find out whether the landlord was notified, and, if the lease requires the owner to keep a key, to try to get the owner a key within two business days. It is not law yet, so check your lease language on keys and lock changes and keep it clear.
Turnover is a team sport
Locks are one part of a good turnover. Fresh paint, clean floors and a working door closer all go into how a unit feels on day one. Schedule the rekey after the cleaners and painters are done, so the new keys are the only ones in circulation when the tenant arrives.
Turnovers in Chelsea and across Boston
HMS has done locksmith work for management companies in Boston and rekeys in Cambridge and Natick. If your properties are north of the city, our Chelsea locksmith page covers what we offer there. Our vans carry key blanks and cutting machines, so several units can usually be handled in one visit.
Frequently asked questions
Do Massachusetts landlords have to change locks between tenants?
The State Sanitary Code requires owners to keep locks that let each unit be secured against unlawful entry, but it does not spell out a rekey at every turnover. Rekeying between tenants is a sensible standard practice because you cannot know how many keys the last tenant had cut.
Trusted Local Network
We like to point readers toward businesses that do careful work in their own trades and markets. Two worth a look:
- A Palm Desert company that offers hand-washed area rug cleaning explains why washing rugs in its own facility, rather than on the floor, gives a deeper clean between tenants.
- A Staten Island glass company that handles custom mirror design and installation for homes in New York and New Jersey shows how much a single upgrade can change a finished unit.
Your Greater Boston Rental Turnover Specialists
If you have a unit turning over soon anywhere in the Boston area, reach our team through the contact page with the address, the number of doors and the move-in date. Call (617) 249-4949 to set up a visit before the new tenant arrives.
HMS Locksmith is based in Allston and serves Boston and nearby communities across Suffolk, Middlesex, Norfolk and Essex counties, including Cambridge, Somerville, Brookline, Newton and Quincy. Learn more about our rekey and master key service, or see what neighbors say in the HMS Locksmith Google reviews before you book.
