What you need to do when you sign as power of attorney

When you sign a document as power of attorney, you are signing on behalf of someone else — the principal — because they have given you legal authority to do so. The way you sign matters. You must write the principal's name first, then add language that shows you are signing as their attorney-in-fact, not on your own behalf. A typical signature looks like this: "Jane Smith, by John Doe, her attorney-in-fact" or "John Doe, as attorney-in-fact for Jane Smith."

The exact format depends on what document you are signing and what the institution receiving it requires. Banks, title companies, and government agencies often have their own rules about how the signature must appear. Before you sign anything, contact the organization that will receive the document and ask them what signature format they need. This one step prevents rejection and delays.

You must also have the power of attorney document itself available when you sign. Some institutions will ask to see it, photocopy it, or keep a certified copy on file. You should never sign as power of attorney without having the actual authority to do so — signing without a valid power of attorney document behind you can expose you to legal liability and may constitute fraud.

Key Takeaways

  • Always sign the principal's name first, followed by language showing you are their attorney-in-fact, such as "by John Doe, her attorney-in-fact."
  • Contact the organization receiving the document before you sign to learn their required signature format, since banks and government agencies have different rules.
  • Keep the original power of attorney document with you when signing, because many institutions will request to see it or keep a copy.
  • Check the power of attorney document itself to confirm it covers the specific type of transaction you are about to sign for.
  • Never sign as power of attorney without a valid, current power of attorney document authorizing you to do so.

How to format your signature correctly

The safest approach is to write out the principal's full legal name, then add a line break or comma, then write "by" or "as," followed by your own name and the words "attorney-in-fact" or "power of attorney." Examples include:

  • Jane Smith, by John Doe, her attorney-in-fact
  • Jane Smith, by John Doe, as power of attorney
  • By John Doe, attorney-in-fact for Jane Smith
  • John Doe, as attorney-in-fact for Jane Smith

Do not straightforward sign your own name. Do not sign the principal's name alone. Both of these will create confusion about who actually authorized the transaction and may cause the document to be rejected or challenged later. If the document has a signature line with a printed title or label — such as "Signature of Principal" or "Signature of Attorney-in-Fact" — follow that label exactly.

Some documents, especially financial or legal ones, may have a separate line for the attorney-in-fact's signature and a separate line for the principal's signature. In those cases, sign only the line designated for the attorney-in-fact. Do not sign the principal's line unless the principal is present and signing alongside you.

Checking the power of attorney document before you sign

Before you sign anything, read the power of attorney document carefully to confirm it actually gives you authority for that specific transaction. A power of attorney may be general (covering most financial and legal matters), limited (covering only specific transactions), or durable (remaining valid if the principal becomes incapacitated). A limited power of attorney for selling a car does not authorize you to sign a mortgage process.

Look for the date the power of attorney was signed and check whether it has an expiration date. Some powers of attorney expire on a specific date; others remain valid until the principal revokes them. If the document has expired, you have no authority to sign, and doing so anyway can result in legal consequences. If you are unsure whether the document is still valid, contact the attorney who drafted it or ask the principal directly.

Also check whether the power of attorney specifies any restrictions or conditions. For example, it might say you can only sign checks up to a certain amount, or only for specific accounts. Signing outside those boundaries means you are acting without authority, even though you hold a power of attorney document.

What institutions will ask to see

Banks, title companies, real estate agents, and government agencies often require you to show the power of attorney document before accepting your signature. Some will ask for the original; others will accept a certified copy. A certified copy is a photocopy that has been stamped and signed by a notary public or court clerk confirming it matches the original.

Many institutions will keep a copy of the power of attorney on file so they have a record of your authority. This protects both you and them. If an institution refuses to accept the power of attorney or says it does not meet their requirements, ask them what format they need — for example, whether it must be notarized, whether it must be on a specific state form, or whether they have their own power of attorney form they prefer you to use instead.

Some organizations, particularly banks and financial institutions, may require the power of attorney to be relatively recent — sometimes no more than a few years old — even if it has no expiration date. This is their internal policy to reduce fraud risk. If your power of attorney is old and an institution rejects it, you may need to have a new one drafted.

When you cannot sign as power of attorney

There are situations where you should not sign as power of attorney, even if you hold a valid document. If the principal is present and mentally capable, they should sign for themselves. Using power of attorney when the principal is able to act is unnecessary and can raise questions about whether the principal truly authorized the transaction.

You also cannot sign as power of attorney if the document has been revoked. A principal can revoke a power of attorney at any time by signing a written revocation and delivering it to you and to any institutions that have a copy on file. If you have any doubt about whether the power of attorney is still valid, contact the principal or their attorney before signing.

Some transactions are straightforward not allowed under power of attorney, regardless of what the document says. For example, you cannot sign a will on someone's behalf, and you cannot vote in elections using power of attorney. If you are unsure whether a particular transaction is allowed, consult an attorney licensed in your state before proceeding.

Keeping records of what you sign

Whenever you sign a document as power of attorney, keep a copy for your records. Write down the date, the name of the document, the institution or person you signed it for, and a brief description of what the transaction was. This creates a clear record of your actions and protects you if questions arise later about whether you had authority or whether you acted appropriately.

If you are managing significant finances or property on behalf of the principal, consider keeping a formal log or spreadsheet. Include the date, the document type, the amount (if applicable), and the purpose. This is especially important if you are serving as power of attorney for an elderly parent or someone with a serious illness, because it demonstrates that you are acting in their interest and not misusing your authority.

Share copies of important documents with the principal if they are able to understand them, and with any family members or advisors who should be aware of major transactions. Transparency reduces the risk of conflict later and shows that you are acting responsibly.

When to ask a lawyer for help

If an institution rejects the power of attorney document or says it does not meet their requirements, contact an attorney licensed in your state. Some organizations have outdated policies or make mistakes, and an attorney can help you understand whether the document is actually valid or whether you need to take additional steps.

If the principal questions whether you should sign something, or if family members disagree about your authority, stop and consult an attorney before proceeding. Signing in the middle of a dispute can expose you to liability even if you have a valid power of attorney.

If you are unsure whether a particular transaction is covered by the power of attorney, or if the document is old or unclear, an attorney can review it and advise you. The cost of a brief consultation is far less than the cost of signing without authority or signing outside the scope of your power.

Frequently Asked Questions

Do I need to notarize my signature when I sign as power of attorney?

It depends on the document and the institution. Some documents, particularly those involving real estate or financial accounts, require notarization. Others do not. Ask the organization receiving the document whether notarization is required before you sign. If it is, you will need to sign in front of a notary public, who will watch you sign and then stamp and sign the document themselves.

What if the power of attorney document is old — does it still work?

A power of attorney with no expiration date remains valid indefinitely unless the principal revokes it. However, some banks and institutions have internal policies requiring the document to be no more than a few years old. If an institution rejects an old power of attorney, ask them what their policy is and whether a new document would be accepted.

Can I sign as power of attorney if the principal is in the hospital or unable to communicate?

Yes, if the power of attorney is durable — meaning it remains valid even if the principal becomes incapacitated. A regular power of attorney ends if the principal becomes unable to make decisions. Check the document to see whether it says "durable" or "springing" (which only takes effect if the principal becomes incapacitated). If you are unsure, contact the attorney who drafted it.

What happens if I sign as power of attorney without actually having the authority to do so?

You could be held personally liable for any losses or damages that result from the unauthorized signature. The other party might sue you, or the principal might take legal action against you. In some cases, signing without authority can constitute fraud or forgery. Always confirm you have a valid power of attorney before signing.

Do I need to tell the principal every time I sign something as their power of attorney?

It is good practice to inform the principal of major transactions, especially if they are mentally capable of understanding. If the principal is incapacitated, you should still keep records and inform family members or a guardian if one has been appointed. Transparency protects you and shows you are acting responsibly.