How to Properly Sign a Power of Attorney Document for Someone

••• Stockbyte/Stockbyte/Getty Images

Related Articles

When someone gives you power of attorney, she is entrusting you to act on her behalf. Some powers of attorney don’t go into effect until the principal, the person granting you the power, can no longer act for herself. Others may go into effect as soon as both of you sign the power of attorney document. When you sign documents for someone else in this capacity, it’s important to make it clear that you’re acting for her, not contracting for any debt or transaction personally.

Have your power of attorney document with you when you sign anything on the principal’s behalf. The entity or person with whom you’re contracting will probably want proof that the principal has authorized you to act for her. Ideally, the principal has already provided copies to all institutions with whom she expects you to deal, but don't count on this.

Read More: How to Remove Someone As Your Power of Attorney

Sign the principal’s name first, not your own. This eliminates any confusion that you’re acting in your own interests or assuming any personal liability for what you’re signing. The principal is actually the one engaging in the transaction.

Sign your own name after the principal’s name, after including the word “by.” This indicates that the principal is engaging in the transaction through you. For example, you would write, “Sally Smith, by Samuel Smith.”

End the signature by indicating that you’re acting under power of attorney. You can do this in one of several ways. After your name, you can write in the words “agent,” “attorney in fact,” “power of attorney” or simply, “POA.” Your final signature should read similar to "Sally Smith, by Samuel Smith, power of attorney."


  • Some banks might want you to sign checks according to their own procedures. Check with the principal’s back to find out how they would like you to sign checks before you risk writing one and having it returned for non-payment.

    If you’re engaging in a transaction of some significant financial impact, the other party might also want you to sign an affidavit as double protection that you’re authorized to act on behalf of the principal. An affidavit simply requires you to sign and attest under oath that the power of attorney is still in full force and the principal has not revoked it. You might also have to attest that the principal has not died or become incapacitated, because these circumstances may invalidate a power of attorney.


About the Author

Beverly Bird is a practicing paralegal who has been writing professionally on legal subjects for over 30 years. She specializes in family law and estate law and has mediated family custody issues.

Photo Credits

  • Stockbyte/Stockbyte/Getty Images