If someone has given you power of attorney, you’re legally authorized to sign documents on their behalf. But signing incorrectly can cause the document to be rejected by banks, title companies, or courts—creating delays and problems for the person you’re helping.
The signature format matters. You can’t just sign your own name or theirs. You need to use the proper legal format that shows you’re acting as their attorney-in-fact under a power of attorney.
Here’s exactly how to sign documents when you have power of attorney, what authority you actually have, and common mistakes that invalidate signatures.
What Is Power of Attorney?
A power of attorney (POA) is a legal document where one person (the principal) authorizes another person (the agent or attorney-in-fact) to act on their behalf.
The agent can sign documents, make financial decisions, handle legal matters, or manage healthcare—depending on what powers the POA document grants.
Why people create powers of attorney:
- Elderly parents who need help managing finances
- Military deployment when someone will be overseas
- Business operations when an owner travels frequently
- Incapacity planning in case of illness or injury
- Real estate transactions when the owner can’t attend closing
The POA only grants the authority specifically listed in the document. If the POA says you can manage bank accounts but doesn’t mention real estate, you can’t sign a deed.
Types of Power of Attorney
Different POAs grant different levels of authority:
General Power of Attorney
Gives broad authority to handle almost all the principal’s affairs—banking, investments, taxes, legal matters, business operations. This type typically ends if the principal becomes incapacitated.
Common uses: Managing affairs while someone travels abroad, handling estate matters when the owner is elderly but still competent.
Limited (Special) Power of Attorney
Grants authority for specific tasks only. Once that task is complete, the POA ends.
Examples:
- Selling a specific property
- Signing closing documents on a real estate transaction
- Managing one particular bank account
- Making healthcare decisions during a specific surgery
Durable Power of Attorney
Remains in effect even if the principal becomes incapacitated. This is the most common type for estate planning.
How it’s different: A regular POA ends when someone becomes mentally incompetent. A durable POA continues, which is exactly when you need it most.
Springing Power of Attorney
Only becomes effective when certain conditions are met—usually the principal’s incapacitation as certified by a doctor.
The problem: Banks and other institutions often resist springing POAs because they require proof that the triggering condition has occurred. This causes delays when you need to act quickly.
How to Properly Sign as Power of Attorney
The signature format is critical. Sign incorrectly and the document will be rejected.
The Correct Format
Principal’s Name, by Agent’s Name, as Attorney-in-Fact
Or:
Principal’s Name, by Agent’s Name, POA
Example: John Smith, by Mary Johnson, as Attorney-in-Fact
Another acceptable format: John Smith, by Mary Johnson, POA
Step-by-Step Signing Process
- Write the principal’s full legal name exactly as it appears on the POA document
- Add the word “by”
- Write your name (the agent’s name)
- Add “as Attorney-in-Fact” or “POA” or “as Power of Attorney”
What NOT to do:
- Don’t just sign the principal’s name
- Don’t just sign your own name
- Don’t sign your name first then the principal’s
- Don’t abbreviate unless the institution accepting the document approves it
State-Specific Requirements
Some states have specific signature format requirements. California, for example, prefers certain wording. Check your POA document—it might specify the exact format to use.
When in doubt, use the full format: “Principal’s Name, by Your Name, as Attorney-in-Fact.” This is universally recognized.
Example Signatures for Different Situations
Bank document: Robert Davis, by Susan Davis, POA
Real estate deed: Margaret Wilson, by Thomas Wilson, as Attorney-in-Fact
Healthcare consent form: Elizabeth Brown, by Michael Brown, Power of Attorney for Healthcare
Always print your name legibly. Illegible signatures cause problems even when the format is correct.
Legal Requirements for Creating a POA
Before you can sign as someone’s attorney-in-fact, they need to properly execute a POA document.
The Principal Must Be Competent
The person granting the POA must be mentally competent when they sign. They need to understand:
- What powers they’re granting
- Who they’re granting power to
- The consequences of the POA
Once someone is already incapacitated, it’s too late to create a POA. That’s why estate planners encourage people to create durable POAs while they’re still healthy.
Written Document Required
POAs must be in writing. Verbal agreements don’t count. The document should clearly state:
- The principal’s full legal name
- The agent’s full legal name
- Specific powers granted
- Whether it’s durable (survives incapacity)
- Any limitations or restrictions
- When it begins and ends (if applicable)
Notarization Requirements
Most states require POA documents to be notarized. The principal signs in front of a notary public who verifies their identity and confirms they’re signing willingly.
Some states also require witnesses—typically two people who watch the principal sign and then sign themselves. Check your state’s requirements.
Why notarization matters: Financial institutions, title companies, and courts won’t accept a POA without proper notarization. It proves the document is authentic and prevents fraud.
Recording Requirements
For POAs used in real estate transactions, you typically must record the POA with the county recorder where the property is located. This creates a public record of your authority to sign deeds and other real estate documents.
Other POAs don’t usually need to be recorded, but you should provide certified copies to any institutions where you’ll be acting—banks, investment companies, insurance companies, etc.
Responsibilities of the Agent
Having power of attorney doesn’t mean you can do whatever you want with someone’s assets. You have serious legal responsibilities.
Fiduciary Duty
You must act in the principal’s best interests, not your own. This means:
- Managing their assets responsibly
- Avoiding conflicts of interest
- Not mixing their money with yours
- Making decisions they would make if they could
- Acting with loyalty, care, and diligence
Violating fiduciary duty can result in lawsuits, criminal charges, and personal liability for losses you cause.
Financial Management
If your POA grants financial authority, you can:
- Pay bills
- Manage bank accounts
- File taxes
- Manage investments
- Buy or sell property (if specified)
- Handle insurance matters
- Deal with retirement accounts
What you cannot do: Make gifts to yourself, change beneficiaries to name yourself, or use their money for your own benefit unless the POA specifically authorizes it.
Healthcare Decisions
A healthcare POA (also called medical power of attorney or healthcare proxy) lets you make medical decisions if the principal can’t communicate.
This is separate from a living will, which states the principal’s wishes. The healthcare POA gives you authority to make decisions not covered in the living will.
Legal Requirements
The legal requirements related to the establishment of a POA are different from one jurisdiction to another, but generally, they include the following:
- Principal’s Competence: The principal must be mentally competent to conclude the POA document.
- Written Document: The POA must be in writing and the principal’s intention must be very clear in it.
- Notarization/Witnesses: Almost all jurisdictions need the POA to be notarized or one or more individuals to witness it.
Notarization Requirements for Power of Attorney Documents
Nearly all states require power of attorney documents to be notarized to be legally valid. Without proper notarization, banks, title companies, healthcare facilities, and courts will reject your POA—leaving you unable to act on the principal’s behalf when they need you most.
Why POAs Must Be Notarized
Prevents fraud – The notary verifies the principal’s identity using government-issued photo ID, making it much harder for someone to forge a POA.
Confirms mental competence – The notary observes the principal during signing and can refuse to notarize if the person appears confused, coerced, or unable to understand what they’re signing.
Creates legal validity – Financial institutions and other entities require notarization before accepting a POA. Without it, your authority to act will be questioned or denied.
What the Notarization Process Involves
- The principal appears before the notary with valid government-issued photo ID.
- Identity verification – The notary checks ID to confirm the principal is who they claim to be.
- Signing in the notary’s presence – The principal signs the POA while the notary watches.
- Notary applies seal and signature – The notary completes the notarial certificate with their official seal and signature.
- Witnesses may be required – Some states require one or two witnesses in addition to notarization.
Get Your Power of Attorney Notarized Online with BlueNotary
Traditional notarization requires scheduling appointments during business hours and traveling to the notary’s location. This creates challenges when the principal has mobility issues, you live in different cities, or you need notarization outside standard business hours.
BlueNotary solves these problems with convenient online notarization:
- Upload the completed POA document to bluenotary.us
- The principal joins a video call with a commissioned online notary
- The notary verifies identity through secure ID checks
- The principal signs electronically while the notary watches
- Receive your notarized POA in 10-15 minutes
Benefits for POA notarization:
- No travel required – Perfect for elderly or mobility-impaired principals
- Flexible scheduling – Available evenings and weekends
- Multi-party convenience – Witnesses can join from different locations
- Cost-effective – $25 versus $75-150+ for mobile notaries
- Fast completion – Done in minutes, not hours or days
This is especially valuable when establishing POA for aging parents, handling emergency situations, or coordinating signing across different locations.
What Happens If Your POA Isn’t Properly Notarized
Financial institutions reject it – Banks won’t let you access accounts without valid notarization.
Real estate transactions fail – Title companies and county recorders won’t accept improperly notarized POAs.
Healthcare facilities refuse to honor it – Hospitals won’t allow you to make medical decisions without notarized healthcare POA.
Court challenges become easier – Un-notarized POAs are easier to contest.
Don’t risk these problems. Ensure proper notarization from the start, whether through traditional in-person notaries or convenient online services like BlueNotary.
Termination
There can be a few instances where a POA can be terminated:
- Revocation by Principal: The principal has the sole power to revoke the POA at any time given that he or she is of sound mind.
- Specified End Date or Task Completion: A limited power of attorney automatically ends after the task has been completed or when the period has expired.
- Death of Principal: The agent’s authority ceases upon the death of the principal unless otherwise provided.
- Court Order: The court may withdraw the POA in case the agent is found guilty of misconduct.
Being familiar with the POA aspects mentioned above guarantees that both the agent and the principal have the knowledge of the respective roles, responsibilities, and legal framework that governs this important arrangement.
Common Mistakes That Invalidate POA Signatures
Wrong Signature Format
The most common mistake is signing incorrectly:
Wrong: Mary Johnson (signing only the agent’s name) Wrong: John Smith (signing only the principal’s name) Wrong: Mary Johnson for John Smith Correct: John Smith, by Mary Johnson, as Attorney-in-Fact
Even well-intentioned signatures in wrong formats get rejected by institutions.
Acting Beyond Your Authority
Read your POA document carefully. If it grants authority over financial accounts but says nothing about real estate, you can’t sign a deed. If it authorizes healthcare decisions but not financial ones, you can’t access bank accounts.
Overstepping your authority can void the actions you take and expose you to legal liability.
Using an Expired POA
Limited POAs often have end dates or expire when specific tasks are completed. Check that your POA is still valid before signing documents.
Not Getting Proper Notarization
If your state requires the POA to be notarized and it wasn’t, the POA isn’t valid. Get it properly notarized before attempting to use it.
Failing to Record When Required
For real estate transactions, you must record the POA with the county before you can sign deeds. Attempting to sign without recording renders the signature invalid.
Mixing Personal and Principal’s Finances
Never commingle funds. The principal’s money should stay in their accounts, separate from yours. Mixing funds makes it impossible to prove you didn’t misuse their money.
Making Decisions That Benefit You
Unless the POA specifically authorizes it, you cannot:
- Give yourself gifts from their assets
- Pay yourself compensation beyond reasonable fees (if authorized)
- Change beneficiaries to favor yourself
- Buy their property at below-market rates
These actions breach your fiduciary duty and can result in serious legal consequences.
Ignoring Communication
Keep the principal informed about major decisions (if they’re competent). Update other stakeholders like family members or co-agents about significant actions. Poor communication causes mistrust and disputes.
Not Understanding “Durable”
A durable POA continues if the principal becomes incapacitated—it doesn’t grant unlimited power. You still can only exercise the authorities specifically granted in the document.
When POA Authority Ends
Your authority as agent terminates when:
The principal revokes it – They can cancel the POA anytime if they’re mentally competent. They should notify you in writing and inform institutions where you’ve been acting.
The principal dies – POA authority ends immediately upon death. At that point, the executor of the estate takes over.
The task is completed – Limited POAs automatically end when the specified task is done.
The expiration date arrives – If the POA has an end date, it terminates then.
A court revokes it – If you abuse your authority, a court can remove you and appoint someone else.
You resign – You can resign by notifying the principal and relevant institutions in writing.
Getting POA Documents Notarized
Since POA documents require notarization in most states, here’s how to get that done:
Traditional notaries at banks, UPS Stores, or through mobile notary services can notarize POA documents. Cost: $10-15 per signature for in-person services, $75-150 for mobile notaries.
Online notary services like BlueNotary let you get POA documents notarized via video call, which is convenient if:
- The principal has mobility issues
- You’re in different locations
- You need it done outside business hours
- You want to avoid travel
Online notarization typically costs $25-40 and takes 10-15 minutes. Most states now allow remote online notarization for POA documents.
The principal must appear before the notary (in person or via video) with valid government-issued photo ID. Witnesses may also need to be present depending on state requirements.
Get your power of attorney notarized online with BlueNotary →
Power of Attorney Conclusions
Acting as someone’s power of attorney is a serious legal responsibility. You must understand the specific powers granted to you, sign documents correctly using the proper format, keep detailed records of everything you do, and always act in the principal’s best interests.
The key points to remember: use the correct signature format (Principal’s Name, by Your Name, as Attorney-in-Fact), only act within the authority granted in the POA document, keep meticulous records, and get the POA properly notarized before attempting to use it.
Mistakes—using the wrong signature format, overstepping your authority, or failing to keep records—can invalidate your actions and expose you to legal liability. When in doubt, consult an attorney about your specific situation rather than guessing.
Take this role seriously. The principal is trusting you with their finances, property, healthcare, or legal matters. Honor that trust by acting carefully, documenting everything, and always putting their interests first.
FAQ
What is a Power of Attorney (POA)?
A power of attorney is a legal document where one person (the principal) authorizes another person (the agent or attorney-in-fact) to act on their behalf. This might be needed when someone is elderly, ill, traveling, or unable to handle their own affairs. The POA specifies exactly what authority the agent has.
What are the different types of Power of Attorney?
General POA grants broad authority over many matters but ends if the principal becomes incapacitated. Limited (Special) POA grants authority for specific tasks only. Durable POA remains effective even if the principal becomes incapacitated. Springing POA only becomes effective when certain conditions are met, usually incapacitation.
What’s the difference between General and Durable Power of Attorney?
A General POA gives broad authority but terminates if the principal becomes incapacitated. A Durable POA continues to work even after incapacitation, which is exactly when you need it most. That’s why durable POAs are more common for estate planning.
What responsibilities does an attorney-in-fact have?
You must act in the principal’s best interests, manage their affairs responsibly, stay within the authority granted in the POA, keep detailed records, avoid conflicts of interest, and never use their assets for your own benefit. You have a fiduciary duty—the highest legal duty of care and loyalty.
What legal requirements are needed to create a POA?
The principal must be mentally competent when signing. The POA must be in writing and clearly state what powers are granted. Most states require notarization, and some require witnesses. The document should specify whether it’s durable and when it begins and ends.
How can a POA be revoked or terminated?
A POA ends when the principal revokes it (if mentally competent), the principal dies, the specific task is completed (for limited POAs), the expiration date arrives, or a court revokes it due to agent misconduct. The agent can also resign by notifying the principal in writing.
What’s the correct way to sign as Power of Attorney?
Use this format: Principal’s Name, by Your Name, as Attorney-in-Fact. Example: “John Smith, by Mary Johnson, as Attorney-in-Fact.” You can also write “POA” instead of “as Attorney-in-Fact.” Never just sign the principal’s name alone or only your own name—that invalidates the signature.
What are common mistakes when acting as POA?
Using the wrong signature format, acting beyond your granted authority, failing to keep detailed records, mixing the principal’s money with your own, making decisions that benefit you instead of them, and poor communication with the principal and family members. Also, not getting the POA properly notarized before trying to use it.
Why does a POA document need to be notarized?
Notarization verifies the principal’s identity, confirms they signed willingly while mentally competent, and creates legal validity. Without notarization, banks, title companies, healthcare facilities, and courts will reject the POA. Most states require notarization for POAs to be legally enforceable.
What records should an agent keep while acting as POA?
Keep records of every transaction—receipts, bank statements, invoices, contracts. Document all decisions made and why you made them. Save communications with the principal, family members, and professionals. Keep account statements and tax returns. These records protect both you and the principal if anyone questions your actions later.
