A service contract or warranty usually says how to end it and how to send formal messages to the company. The notice clause sets out where those messages go, by what method, and when they count as received. Read it before you need it. A cancel request or a claim sent to the wrong address can sit unread while the time limits in the contract keep running.
Look for a heading such as Notice, Notices, Cancellation, How to Make a Claim, or Contact. Some contracts put the notice rule in the general terms at the back, and others repeat it beside the cancellation paragraph. Mark every mailing address, email address, web form, or phone line the paper names, and note which one it gives for each kind of message.
In the clause, check the following.
Which address is listed for cancellation requests, and whether claims go to the same address. Many contracts separate the two, so a cancel letter sent to the claims desk may not be the notice the contract requires.
Whether email counts. If the clause does not name an email address as a valid route, do not assume a message sent there has been received as notice.
Whether the clause requires a tracked or certified letter, a signed delivery receipt, or a copy sent to a named party. A plain letter may fall short of a stated requirement.
When a notice is treated as given. Some clauses count the day it is sent, and others count the day it arrives. Ask which rule applies before you rely on either.
Whether the company can change its address, and how it tells you when it does. A clause that allows changes by posting a notice online is different from one that requires a letter to you.
Ask the seller or the company, in writing, to confirm the notice address for cancellation and for claims. Keep a copy of every message you send, a note of the method you used, and any proof of delivery. If the company later says it never received a notice, that record is what you will need to show what happened. What the printed clause says controls the question. What a salesperson or a phone agent told you does not replace it.
This guide does not summarize any one state's notice rules. Each state page on this site names the regulator and the statute or program cited for that state, and says whether a roster is published. If you are in Florida, start with the Florida rules and roster page, then read the contract itself, since the state page does not replace the paper you signed.