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Generally yes. A signature stamp counts as your signature when you authorized it, and courts have long accepted stamped signatures on business letters and contracts. Some recipients refuse them anyway: banks, government agencies, and notaries often require a handwritten signature, so confirm before you stamp anything bound for one of them.
This is general information, not legal advice.
A signature is about intent, not penmanship. When you authorize the stamp and intend it to stand as your signature, courts in the US and Canada have treated stamped signatures as binding for well over a century: on contracts, business correspondence, checks, and corporate documents. Companies stamp thousands of routine letters, invoices, and form notices this way. The key legal ingredient is authorization: the stamp has to be used by you or by someone you allowed to use it, for the purpose you allowed. An old but durable rule of thumb is that a stamped signature is as good as a handwritten one unless a specific law or the other party's rules say otherwise.
| Recipient or document | Why hand-sign |
|---|---|
| Banks and lenders | Many compare signatures against the card on file and reject stamps. |
| Government agencies | Forms often specify an "original signature" requirement. |
| Notarized documents | A notary must witness you signing; a stamp defeats the purpose. |
| Wills and estate documents | Formal execution rules usually demand handwriting. |
| Anything where the other side asked for ink | Their rule wins, whatever the law allows. |
The pattern: wherever someone will scrutinize the signature itself, a stamp invites an argument you do not need. For routine business mail, nobody looks twice. For anything adversarial, formal, or financial, pick up the pen.
Treat a signature stamp like a signing authority, because that is what it is. Keep it locked up, limit who can use it, and be explicit about what it may be used for: a stamp authorized for routine correspondence should never touch a contract. If the stamp is lost or an employee leaves with access to it, tell your bank and key counterparties the way you would for a compromised checkbook. An unauthorized stamped signature can still bind you if the other party reasonably believed it was authorized, which is exactly why control matters.
There is no physical stamp involved. Your signature goes into the letter itself: type your name in a signature block, or place a scanned signature image in the document you provide. The letter is printed exactly as quoted, single-sided on US Letter paper, and mailed in a double-window envelope. For formal letters, a typed signature block with your printed name and title reads as professional; for personal letters, an image of your actual handwriting keeps the personal touch.
Yes, if you authorized them, and this is where most signature-stamp trouble starts. An assistant stamping routine correspondence with your permission is standard business practice. But authorization has boundaries: it should be explicit, it should name what the stamp may be used for, and it should be revocable the moment the person leaves the role. Never let the authorization live as an unspoken understanding. And keep the circle small: every additional person with access is another person whose misuse you might have to explain. If a dispute ever arises, the first question will be who was allowed to use the stamp and for what, so have an answer written down.
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.
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