What is a Letter of Authorization (LOA)? [With Examples]

Published 22 May 2025

Letter of Authorization (LOA): Definition, Uses & Common Mistakes

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When considering business agreements or authorizations, you may first imagine complicated contracts or legal terms. However, not all business permissions are hard to understand. A Letter of Authorization (LOA) simplifies the process by clearly outlining who is granted permission, what actions they can take, and for how long.

Whether used for temporary assignments or ongoing responsibilities, a LOA ensures that business operations can continue smoothly even when individuals are unavailable. By clearly stating the authority given, the LOA helps avoid confusion and ensures everyone understands their roles. It allows businesses to keep running smoothly, even when the main person in charge is not available.

Highlights:

A Letter of Authorization (LOA) is a formal document that allows a person or organization to act on behalf of another.
LOAs are essential in business because they ensure legal permission, promote accountability, and build trust.
LOAs are commonly used when employees are unavailable, during third-party business activities, or when someone else needs to make decisions on behalf of the organization.
Common mistakes when creating an LOA include vague wording, missing expiration dates, unsigned documents, and not following legal requirements.

What is a Letter of Authorization?

A Letter of Authorization (LOA) is a formal document that permits one party or person to act on behalf of another in specific matters. In other words, LOA is a tool that delegates legal authority or power, permitting someone to perform or take action on your behalf. It outlines the scope, duration, and nature of the authority given to the authorized party.

LOAs are commonly used in business transactions, legal matters, and other situations. This document helps clarify roles and ensures smooth operations by specifying the actions the authorized person is permitted to do.

Why LOAs Matter in Business?

A LOA helps a business define who can represent the company, ensuring transparency and accountability in its operations.

Highlight Trust: LOAs build trust between businesses by confirming that one party has the authority to make decisions or act on behalf of another.
Accountability: Ensures the authorized person is responsible for their actions.
Legal Compliance: LOAs help businesses stay compliant with regulations by ensuring that all actions taken on behalf of the company are properly authorized.
Conflict Prevention: With a well-documented LOA, businesses can prevent misunderstandings about who has the authority to make decisions or take actions.

When is an LOA Used in Business?

An LOA (Letter of Authorization) is used in business when a company needs to grant permission to a third party to perform a specific task. It is commonly used for porting phone numbers or authorizing vendors to access business information or services.

1. Porting Business Phone Numbers

An LOA is used when a business wants to port phone numbers from one service provider to another. It authorizes the current provider to release the phone numbers to the new provider.

Without an authorized LOA document, the porting process cannot legally proceed. By submitting an LOA, businesses authorize the number transfer in a secure and controlled manner, helping to prevent delays during the porting process.

Information Needed for Porting Business Phone Numbers via an LOA

Your name, billing address
Current service provider's details
Phone number to be ported
New service provider's details
Account number with the current service provider
Copy of current phone bill
A statement authorizing the porting process
Signatures from the business or an authorized person

Note:

You can use a single LOA to port several numbers from the same carrier or service provider. However, if you are porting numbers from different providers, you need a separate LOA for each one.

Sample of LOA for Porting Business Phone Numbers

LETTER OF AUTHORIZATION FOR NUMBER PORTING

As the authorized representative of [Customer Name] (“Customer”), I hereby authorize [New Service Provider Name] to act on behalf of the customer to port the telephone number(s) listed below. This includes granting permission to contact and coordinate with our current telecommunications provider to facilitate the porting process.

I certify that the customer has full rights to the telephone number(s) being ported and that the information provided here is accurate. I acknowledge that the numbers must remain active with the current provider until the porting process is completed.

Customer Information

Customer Name: ___________________________________________

Customer Address: _________________________________________

City: _____________________ State/Province/Region: _____________________

Postal Code/Zip: _____________________ Country: _____________________

Customer Email Address: ___________Customer Phone Number: __________________

Representative Information

Print Name: _____________________

Title: _____________________

Current Service Provider (Losing Carrier): _____________________

Requested Port Date: _____________________

Authorized Customer Signature: _____________________

Signature Date: _____________________

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2. Authorizing Third-Party Vendors or Service Providers

Businesses use an LOA to formally grant third-party service providers the authority to act on their behalf. This document helps protect both parties by outlining the responsibilities and limits of the authority granted.

By issuing an LOA, the business ensures that the third party has the legal permission to handle specific functions, such as managing information or executing operations.

Information Needed for Authorizing Third-Party Vendors via an LOA

Third-party service provider name and contact details
Specific tasks or permissions granted to the third party
Duration or time frame of authorization
Any limitations or restrictions on the authorization
Signatures from the business or an authorized person
Sample of LOA for Authorizing Third-Party Vendors or Service Providers

Sample of LOA for Authorizing Third-Party Vendors or Service Providers

[Your Name]
[Your Address]
[City, State, PIN Code]
[Email Address]
[Phone Number]

[Date]

To,
[Recipient's Name]
[Recipient's Designation]
[Company/Organization Name]
[Company Address]
[City, State, PIN Code]

Subject: Authorization for Legal Representation
Dear [Recipient's Name],

I, [Your Name], residing at [Your Address], hereby formally authorize [Authorized Person’s Name], residing at [Authorized Person’s Address], to act on my behalf in all legal matters related to [specific purpose, e.g., signing documents, representing me in legal proceedings, etc.].

This authorization includes, but is not limited to, the authority to sign documents, appear in legal proceedings, and take all necessary actions to protect and enforce my legal rights. [Authorized Person’s Name] is empowered to act fully in my stead as required.

This authorization will remain in effect starting [start date], and will continue until [end
date/indefinitely], unless explicitly revoked by me in writing.

Thank you for your prompt attention and cooperation.

Sincerely,
[Your Signature (if sending a hard copy)]
[Your Name]

Common Mistakes to Avoid When Using a Letter of Authorization in Business

To ensure the LOA achieves its outcome, you must avoid common mistakes like using an unauthorized signature, lacking specificity, or failing to keep records.

Lack of Specificity: Clearly define the tasks, limits, and responsibilities to avoid confusion or misuse.
Missing Validity Dates: Without a start and end date, the LOA might be used beyond its timeframe. So, always include the duration of validity to limit the authority's duration.
No Signature or Improper Signatory: A missing signature or one from someone without the proper authority can make the document invalid.
Failing to Identify All Parties Clearly: The LOA should clearly state the names and roles of all involved parties, including the authorizer and the authorized person.
Lack of Record Keeping: You must keep a copy of the LOA to prevent conflicts, compliance issues, or loss of trust.

Conclusion

A letter of authorization (LOA) is used when a person or organization cannot perform a specific task and needs someone to handle the responsibilities. The LOA clearly defines what actions are allowed, ensuring both parties understand their roles and the limits of the authority given. By specifying the limits of the authority granted, the LOA helps avoid misunderstandings and protects the interests of all parties involved.

With Calilio, businesses can easily port any type of number, local, toll-free, mobile, or VoIP, without losing their identity or disrupting communication. Our cloud-based business phone system smooths the number porting process while offering advanced features, like HD call quality and real-time analytics.

Frequently Asked Questions

How long is a letter of authority valid?

A Letter of Authority is typically valid for 12 months from the issue date. However, the duration can be different depending on the industry and purpose.

What is the reason for a letter of authorization?

An LOA allows someone to act on behalf of another person or entity for specific tasks, such as business transactions, legal matters, porting numbers, banking, or document collection.