The notice period is the countdown clock on your exit. If the contract says "90 days written notice," you have to tell the vendor at least 90 days before the term ends, or you lose the right to leave cleanly that cycle.
It matters most when it is paired with auto-renewal. A short window (30 days) buried in a contract that renews for a full year is a trap: blink and you have re-upped. A long window (90+ days) actually helps you, because it gives your team time to evaluate alternatives and negotiate from strength.
Watch for two things: how the notice must be delivered (email may not count if it demands "written notice by certified mail"), and whether the clock is measured from the renewal date or the invoice date.
"Customer may terminate for convenience upon ninety (90) days' prior written notice, delivered to the address in Section 12."
Worried about this clause in your own contract?
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