What Is a Letter of Authority (LOA)?

A Letter of Authority (LOA) is a legal document that allows a customer to formally authorise a third party to act on their behalf within agreed limits. In telecommunications, an LOA is commonly required to request changes such as number porting or service transfers.

An LOA gives clarity and confidence to all parties by confirming who is authorised to act, what actions they can take, and which services are covered.

Why Is a Letter of Authority Required?

Telecoms providers will only accept instructions from an authorised party. An LOA confirms that permission has been given and helps prevent unauthorised changes to services.

It is typically required when:

• Porting phone numbers between providers

• Migrating voice services during an office move

• Replacing or consolidating phone systems

• Transferring services from a previous supplier

What Information Does an LOA Include?

To be accepted, an LOA must match the details held by the current (losing) provider. This usually includes:

• Company name and registered address

• Service address

• Account or billing reference

• The numbers or services being transferred

• Authorised signatory details

Accuracy is important, as mismatched details can delay or reject a port request.

Help Completing the LOA

Several sections of the LOA must be completed carefully. To avoid delays, we generally offer to help complete the form with you.

It is often useful to provide:

• A recent bill from the current provider

• Confirmation of the address and company details they hold

This helps ensure the port request matches the provider’s records.

What Happens After the LOA Is Submitted?

Once the LOA is received and verified:

• The port request can be submitted to the losing provider

• Timelines and dependencies are confirmed

• Any issues or mismatches can be addressed early

This reduces the risk of delays or failed port attempts.

Summary

A Letter of Authority allows a customer to authorise a third party to act on their behalf when making changes to telecoms services. It is a standard requirement for number porting and service migrations and helps ensure changes are carried out correctly and securely.

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