LetterAgent
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Mail your letter to the carrier's correspondence or customer service mailing address, not to a retail store, using the address listed on your bill or the carrier's contact page. Include your full name, account number as shown on your bill, the phone number involved, a clear description of the issue, and what outcome you want, and keep a copy with proof of mailing.
Retail stores sell phones and plans, but they do not handle billing disputes, account cancellations, or formal complaints. A letter sent to a store may be filed, forwarded slowly, or lost, because store staff are not the team that can change an account. Carriers publish separate correspondence addresses for billing, cancellations, and legal notices, and those addresses route to the teams that actually hold account records. Your bill, or the carrier's contact page, is the best source for the current address: do not guess from a store address or an old letterhead.
Some carriers list different addresses for different purposes. A billing dispute may go to one address, a cancellation request to another, and a legal notice to a third. Using the wrong one does not always kill the letter, since large carriers forward mail internally, but it can add weeks. If the carrier lists a specific address for your purpose, use it exactly, including any department name or mail code.
Start with identification the carrier can match to an account: your full name as it appears on the account, the account number from your bill, and the phone number or numbers involved. Add the billing period or statement date for a charge dispute, and quote the charge exactly as it appears. For a cancellation, state the phone number, the date you want service to end, and whether you want written confirmation sent to you, and by what method.
State the outcome you want in one sentence: a corrected bill, a refund of a specific charge, cancellation on a specific date, or a written explanation of a charge. Attach nothing original: quote account details inside the letter, and keep copies of bills, contracts, and earlier correspondence. If you are disputing a charge, say when you first noticed it and whether you already called about it, with dates if you remember them. That history helps the reviewer see that this is not the first contact.
| Purpose | Send to | Include |
|---|---|---|
| Billing dispute | Billing correspondence address | Account number, statement date, charge quoted |
| Cancellation | Cancellation address on bill or site | Phone number, end date, confirmation request |
| Service complaint | Customer service correspondence address | Dates, places, what happened |
| Deceased account holder | Address for estate or transfer requests | Account details, your relationship, supporting papers |
| Formal or legal notice | Legal notice address, if listed | Full account details, clear demand, deadline |
Do not include a full Social Security number, Social Insurance Number, or complete payment card number in a letter to a carrier. An account number and a phone number are enough for the carrier to find the account, and extra identity numbers on paper only add risk if the letter goes astray. If a carrier form asks for more, call the carrier first and ask whether it is required for a mailed request.
Also be careful with timing. A cancellation letter mailed today does not necessarily cancel service today: carriers may process mailed cancellations over days, and billing may continue until the request is processed. If you need service to end by a specific date, mail early, ask for written confirmation, and keep the mailing receipt. For anything where a missed deadline could cost money, such as a contract end date, use a tracked service so you can show when the carrier received it.
Yes, for carriers with US or Canadian correspondence addresses. Describe the letter to your AI assistant, approve the exact quoted price, and it is printed and mailed in a double-window envelope. For a billing dispute or cancellation, ask about the certified or registered option, since proof of delivery can matter if the carrier later says the letter never arrived. Letters are single-sided with no inserts, so quote the key bill details inside the letter itself.
Ready to mail it? Send your letter with LetterAgent: describe it to your AI assistant, approve the exact quoted price, and it is printed and mailed.
LetterAgent is a working name. Prices include print, postage, and our service fee. US prices in USD, Canadian prices in CAD (Canadian prices exclude applicable sales tax, added at checkout). Currently in private testing.
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