Most cleaning transitions go wrong in one of two ways: notice is served before a replacement is ready, leaving the building uncovered, or the outgoing vendor is kept too long and quality collapses during the notice period.
The fix is sequence. Everything below assumes you want zero uncovered nights and no scramble on the first morning after the change.
Read the termination clause before anything else
Most commercial janitorial agreements require 30 to 60 days written notice. Many auto-renew for another full term if that notice window is missed, which means the practical deadline for deciding is often two to three months before the date you actually want the change.
Check three specifics: the required notice period, the delivery method the contract demands, and whether the agreement auto-renews. Notice delivered by email when the contract requires certified mail has been the cause of more than one accidental renewal.
Select the replacement before you serve notice
Run the full replacement process first: walkthrough, written specification, pricing, insurance verification, and a signed agreement with a start date. Only then serve notice on the incumbent, timed so the new vendor's first night falls immediately after the outgoing vendor's last.
This sequence has a second benefit. A vendor who knows they are being replaced has little incentive to maintain standards through a 60 day notice period. Keeping that window as short as the contract allows limits the decline.
Verify insurance before the first shift, not after
Confirm the incoming vendor's certificate of insurance is active, that the named insured matches the entity signing your contract, that limits meet your requirements, and that the additional insured and waiver of subrogation endorsements are actually attached.
Request the certificate from the vendor's broker rather than accepting a forwarded PDF. This is the single step most often skipped under time pressure, and it is the one that matters if something happens during week one.
Recover access on the final night
Collect keys, badges, fobs, and any master or grand master on the outgoing vendor's last shift, and have it happen in person rather than by promise. Then change alarm codes regardless of what was returned, because copies are easy to make and impossible to audit.
Keys and master keys
Recover and count against your issuance log. Re-key if any master is unaccounted for.
Badges and fobs
Deactivate in the access system rather than only collecting the physical credential.
Alarm codes
Change them, and issue the incoming vendor a distinct code so activity is attributable.
Supply closets and equipment
Confirm what belongs to the building and what leaves with the vendor before the last night, not during it.
Plan the first two weeks deliberately
A new crew does not know your building. Expect a learning period and manage it with structure: walk the site with the new supervisor during the first week, inspect against the written specification rather than against impressions, and log deficiencies in writing with a defined correction window.
Tell occupants the change is happening. Most complaints in week one are about unfamiliarity rather than quality, and a short notice to tenants prevents a wave of tickets that makes a normal transition look like a failure.
A workable timeline
Working backward from the target start date: begin vendor selection 90 days out, complete walkthroughs and pricing by 75 days, verify insurance and sign by 65 days, serve notice at the contractual deadline, confirm the overlap and access plan two weeks out, and run the changeover with the new vendor starting the night after the incumbent's last shift.