The correct way to sign depends on whether you have a durable power of attorney or a limited one
When you sign a document as power of attorney, you are signing on behalf of someone else — the principal. The way you write your signature matters legally. If you sign your own name alone, you may be held personally liable for the contract. If you sign it wrong, the document may not be recognized as valid.
The safest format is to write the principal's name first, then add "by" and your own name, then your title. For example: "John Smith, by David Reeves, as Power of Attorney" or "John Smith, by David Reeves, Attorney-in-Fact." Some documents ask you to initial instead of sign — follow those instructions exactly.
Before you sign anything, make sure you have the actual power of attorney document with you. Banks, title companies, and other institutions often want to see it. Some will make a copy for their records. If the document is old or the institution is unfamiliar with it, they may ask for a certified copy from the court or the attorney who drafted it.
Key Takeaways
- Sign the principal's name first, followed by "by" and your name and title, so the signature shows you are acting on their behalf, not your own.
- Always have the original power of attorney document with you when you sign, because institutions often require proof that you have the authority to do so.
- Different institutions have different signature requirements — banks may ask for initials only, while real estate transactions may require a full signature with a notary present.
- If you sign in your own name alone without the principal's name, you may be personally liable for the contract or obligation.
- A certified copy of the power of attorney may be required if the document is more than a few years old or if the institution does not recognize the original.
The signature format that protects you legally
The standard format is: Principal's Name, by Your Name, Your Title. For example:
Margaret Chen, by Robert Chen, as Power of Attorney
Or:
Margaret Chen, by Robert Chen, Attorney-in-Fact
The word "by" is the key. It tells anyone reading the document that Robert Chen did not sign on his own behalf — he signed on Margaret Chen's behalf. Without it, the signature is ambiguous.
Some documents have a line that says "Sign here as Power of Attorney" or "Sign here on behalf of [Principal's Name]." In those cases, follow the instruction on the form. If there is no instruction, use the format above. Never sign only your own name when you are acting as power of attorney, even if the space is small.
When you need the power of attorney document present
Banks, title companies, insurance companies, and government offices almost always ask to see the power of attorney document before they will accept your signature. They want to verify that you actually have the authority to sign. Some will photocopy it. Others will scan it into their system.
Bring the original document, not a photocopy, unless the power of attorney specifically says "copies are as valid as the original." If you only have a photocopy, ask the institution whether they will accept it. Many will not.
If the power of attorney is more than three or four years old, the institution may ask for a certified copy from the court that issued it or from the attorney who drafted it. This is especially common in real estate transactions and banking. A certified copy costs money — usually $10 to $25 — but it removes doubt about whether the document is still valid.
Real estate transactions and notary requirements
When you sign a deed, mortgage, or other real estate document as power of attorney, the signature almost always must be notarized. The notary watches you sign and verifies your identity with a photo ID. They then stamp and sign the document themselves.
The title company or real estate attorney handling the transaction will tell you whether notarization is required. If it is, you cannot sign the document yourself and have someone else notarize it later — the notary must be present when you sign.
Some title companies have their own notary on staff. Others will direct you to a notary public in your area. UPS stores, banks, and some law offices offer notary services for a small fee, usually $5 to $15 per signature. Call ahead to confirm they are available and ask what ID they need.
Bank accounts and financial institutions
Banks have their own signature requirements, and they vary. Some banks ask you to sign checks and withdrawal slips in the format described above. Others ask you to initial only. Some require the power of attorney document to be on file before you can sign anything.
Before you open an account or sign a check as power of attorney, contact the bank and ask what they need. Bring the power of attorney document with you when you visit. The bank may ask you to sign a separate authorization form that gives them permission to honor your signature.
If the principal's name is on the account but you are signing on their behalf, write their name first, then "by" and your name. If you are signing a check, the back of the check may have limited space — sign as neatly as you can in the format above, or ask the bank whether they will accept initials instead.
What happens if you sign it wrong
If you sign only your own name without the principal's name, the other party may assume you are signing on your own behalf. This can make you personally liable for the contract, debt, or obligation. For example, if you sign a loan agreement in your name alone, the lender may pursue you for repayment, not the principal.
If the signature is unclear or ambiguous, the institution may refuse to accept the document and ask you to sign again. This is especially common with banks and title companies, which are cautious about liability.
If you have already signed a document incorrectly, contact the institution that received it and ask whether you can sign a corrected version. Do not try to cross out the old signature and write a new one — that makes the document look altered and may make it invalid. A fresh signature on a new copy is cleaner and safer.
Power of attorney documents that limit your signing authority
Some power of attorney documents restrict what you can sign. For example, a limited power of attorney might say "This person may sign real estate documents only" or "This person may sign checks up to $5,000." Read the document carefully before you sign anything.
If the document you are asked to sign falls outside your authority, do not sign it. Signing outside the scope of your power of attorney can expose you to legal liability and may be considered fraud. If you are unsure whether you have the authority, contact the attorney who drafted the power of attorney or ask the principal to clarify.
Some institutions will ask you to confirm in writing that you are acting within the scope of your authority. Answer honestly. If you are not sure, say so — it is better to ask than to sign and create a problem later.
Frequently Asked Questions
Do I need to notarize my signature every time I sign as power of attorney?
No. Notarization is required for real estate documents, some financial transactions, and documents filed with the court. For everyday checks, bills, and routine paperwork, notarization is usually not needed. Ask the institution or the person requesting the signature whether notarization is required before you sign.
What if the power of attorney document is very old — is it still valid?
That depends on the type of power of attorney and the institution. A durable power of attorney remains valid even if it is old, unless the principal revoked it. However, banks and title companies often ask for a certified copy if the document is more than three or four years old. Contact the institution first to ask what they need.
Can I sign a document as power of attorney if the principal is present?
Yes, but the principal's presence does not change how you sign. You still write the principal's name first, then "by" and your name. The principal does not need to sign as well unless the document requires both signatures — for example, some bank forms ask both the principal and the power of attorney to sign.
What if I make a mistake while signing as power of attorney?
Do not try to correct it on the same document. Ask for a fresh copy and sign that one instead. Crossed-out or altered signatures can make a document invalid or raise questions about its authenticity. A clean signature on a new copy is always safer.
Do I need to show my ID when I sign as power of attorney?
If a notary is present, yes — they will ask for photo ID. For other signatures, it depends on the institution. Banks often ask for ID. For routine paperwork, ID is usually not required, but you should always be ready to show it if asked.