What you need to do when you sign on someone else's behalf
When you sign a document as someone's power of attorney, you are signing in their name, not your own. The signature line should show their name, followed by your name as the person authorized to sign. The exact format depends on the type of document and what the other party requires, but the core rule is the same: make clear that you are signing as their agent, not as yourself.
Most documents have a signature block that tells you where to write. If it does not specify how an attorney-in-fact should sign, use this format: write the principal's name (the person who gave you the power of attorney), then write "by" or "as attorney-in-fact for," then write your own name. Some organizations have their own signature blocks and will tell you exactly what they want. Always ask before you sign if you are unsure.
Key Takeaways
- Sign the principal's name first, then add "by [your name], attorney-in-fact" or follow the format the document specifies.
- Have a copy of the power of attorney document with you when you sign, because many organizations will ask to see it before accepting your signature.
- Some documents require the signature to be notarized, which means a notary public must watch you sign and verify your identity.
- Banks, real estate offices, and government agencies often have their own rules about how an attorney-in-fact must sign, so call ahead and ask.
- Keep a record of every document you sign on the principal's behalf, including the date, what it was for, and which power of attorney you used.
The correct signature format for power of attorney
The standard way to sign is to write the principal's name on the signature line, then add your role and name below or beside it. For example: "John Smith, by Sarah Chen, attorney-in-fact" or "John Smith / Sarah Chen, Power of Attorney." The exact wording matters less than making it clear that John Smith is the person the document is about and Sarah Chen is signing on his behalf.
Some documents have a printed signature block that says "Principal" or "Grantor" on one line and "Attorney-in-Fact" on another. If that is the case, sign your name on the attorney-in-fact line and write the principal's name on the principal line. Do not sign the principal's name yourself unless the document explicitly tells you to do so.
If you are signing a check or bank document, the bank may have a specific format they require. Call the bank before you sign and ask how they want the signature to appear. Some banks want the principal's name first, others want your name first with "as POA" or "as attorney-in-fact" after it. Getting this right the first time prevents the document from being rejected.
When you need to show the power of attorney document
Most organizations will not accept your signature without seeing a copy of the power of attorney that gives you the authority to sign. Before you sign anything, bring the original power of attorney or a certified copy with you. The other party will usually make a photocopy for their records.
Banks are the most strict about this. They often require a certified copy of the power of attorney, which is a copy that has been stamped and signed by a notary or court clerk to confirm it is a true copy of the original. Some banks will accept a regular photocopy, but call ahead to ask what they need. If you show up without the right version, they may refuse to process the document.
Real estate transactions, government agencies, and legal documents almost always require you to produce the power of attorney. Keep multiple certified copies on hand if you will be signing documents regularly. You can get certified copies from the notary who notarized the original power of attorney, from the court clerk in the county where it was filed, or from the attorney who drafted it.
Notarization requirements for attorney-in-fact signatures
Some documents require a notary public to watch you sign and verify your identity. This is common for real estate deeds, financial documents, and legal paperwork. If the document says "notarize" or "notarization required," you cannot sign it alone—you must go to a notary and sign in front of them.
When you go to the notary, bring your government-issued photo ID and the power of attorney document. The notary will ask you to sign the document in front of them, and they will then stamp and sign the document to confirm they watched you sign and checked your ID. The notary is confirming your identity, not the validity of the power of attorney itself.
Some notaries will ask to see the power of attorney to make sure you have the authority to sign. This is reasonable, and you should show it to them. However, the notary is not responsible for verifying that the power of attorney is real or valid—that is the responsibility of the organization receiving the document. If the notary seems unsure, ask them to notarize it anyway and let the receiving organization decide whether to accept it.
What to do if the document has special requirements
Banks, insurance companies, and government agencies sometimes have their own signature requirements that differ from the standard format. Before you sign, contact the organization and ask how they want the signature to appear. Some will email you a sample signature block or instructions. Others will tell you to sign however you want as long as you include the power of attorney document.
If an organization refuses to accept your signature because of the format, ask to speak to a supervisor or the legal department. Explain that you signed according to standard power of attorney practice and that you have the power of attorney document to prove your authority. Most organizations will accept the signature once they confirm the power of attorney is valid.
If an organization continues to refuse, you may need to contact the attorney who drafted the power of attorney or ask the principal to contact the organization directly. Some organizations have outdated policies or are overly cautious, and a call from the principal or their attorney can often resolve the issue quickly.
Keeping records of documents you sign
Every time you sign a document as attorney-in-fact, write down what you signed, the date, and which power of attorney you used. This creates a record for the principal and protects you if there are questions later about whether you had the authority to sign.
Keep a straightforward log with the document name, date signed, organization or person you signed it for, and a brief note about what it was for. For example: "Bank of America check deposit, March 15, 2024, General Power of Attorney." Store this log with your copies of the power of attorney documents. If the principal ever questions a signature or if there is a dispute, you will have proof of what you signed and when.
Also keep copies of the signed documents themselves, if possible. Some organizations will give you a copy, others will not. If you can get a copy, file it with your records. This is especially important for financial documents, real estate transactions, and legal paperwork.
Common mistakes to avoid when signing
The most common mistake is signing your own name instead of the principal's name. Remember: you are signing on their behalf, so their name goes on the signature line. Your name goes in the "attorney-in-fact" or "by" line. If you sign your own name as if you are the party to the document, the signature may be invalid.
Another mistake is signing without the power of attorney document with you. Many organizations will reject the signature if you cannot show them the power of attorney. Do not assume they will accept it—bring the document every time.
A third mistake is signing a document that is outside the scope of the power of attorney. If the power of attorney only covers financial matters, you cannot sign a healthcare document. If it only covers real estate, you cannot sign a bank check. Always read the power of attorney carefully to confirm you have the authority to sign before you put pen to paper. If you are unsure, ask the principal or contact an attorney.
Frequently Asked Questions
Do I have to use the principal's signature or can I use my own?
You sign your own name, but you write the principal's name on the signature line first. The format is: Principal's Name, by Your Name, Attorney-in-Fact. You never forge the principal's signature or try to write their name in their handwriting. The signature must be yours, and it must be clear that you are signing as their agent.
What if the document does not have a space for "attorney-in-fact"?
Sign the principal's name on the signature line, then write "by" or "as attorney-in-fact for" and your name below it or in the margin. If there is truly no space, write it on the back of the document or on a separate page attached to it. The key is making it clear that you are signing as their agent, not as yourself.
Can I sign electronically as an attorney-in-fact?
Yes, but the process depends on the document and the organization. Some banks and government agencies allow electronic signatures from an attorney-in-fact, while others require a wet signature (pen on paper). Ask the organization before you sign. If they allow electronic signatures, they will usually tell you how to format your name in the signature field.
What happens if I sign a document I am not authorized to sign?
The signature may be invalid, and the principal could be held responsible for the document anyway. You could also face legal liability if the principal suffers a loss because of your unauthorized signature. Always confirm you have the authority to sign before you do it. If you are unsure, ask the principal or contact an attorney.
Do I need to tell the principal every time I sign something?
Yes. The principal has the right to know what documents you are signing on their behalf. Keep them informed and provide them with copies of signed documents. If the principal objects to a signature you made, stop signing documents and discuss it with them when ready. Your role is to act in their best interest, not to make decisions without their knowledge.