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Provide direct access to employees and departments with 4-digit extensions.

Direct Access to People and Departments

“Or if you know your party’s extension, you may dial it now…” Extensions are an easy and cost-effective way to give callers direct access to people and departments that don’t have a dedicated phone number. Callers simply dial the person or department’s 4-digit extension from your company phone number’s welcome menu.

Extensions direct access

Better Branding for Your Business

Direct phone numbers for certain individuals and teams can be a great choice in some scenarios, but in others, they can detract from the simplicity of having one main company phone number. Extensions give you the best of both worlds – strong, consistent branding across a single phone number with easy, direct access to any person or team.

Business card example with business phone extension

Make Changes to Your Extensions at Any Time

Easily add or remove an extension whenever you need, right from the Tresta web app. You have up to 9,000 extensions available to use, and extensions are completely free – like all of Tresta’s features.

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It’s Easy –
Let’s Start Here

Tresta makes it easy to get a new phone number or transfer your current one.

Frequently Asked Questions

What is the difference between a user and an extension?

Users are individuals with a unique login to your account. Extensions are four-digit numbers that can be assigned to users, user groups and forwarding numbers for use in auto attendants.

How can I configure extensions on my Tresta phone system?

All extensions can be easily configured in the Tresta web app by a System Admin on your account.

Is there a limit to the number of extensions I can create?

You can have up to 9,000 extensions on your account.

How do callers use extensions?

Callers can dial an extension from within any auto attendant. To make sure your callers are aware of the option, the audio file you play should contain instructions to callers to press an extension number at any time to be routed to the person or department they wish to reach.

Can I pick the extension numbers I want?

Extension numbers start at 1000 and end at 9999. You can pick the exact extension numbers you’d like from within this range.

Can I give a user group an extension number?

Yes, you can assign an extension number to a user group to make it easier for callers to reach the user group directly.

I have other questions. Who can help me?

If you have additional questions, we’d love to talk with you. Our product specialists are available 24/7 – visit our contact page for details on how to reach us by phone, chat, and email.

Loved by Customers

At Tresta, you’re our passion. We’re constantly striving to make our business phone system even better, because nothing makes us happier than seeing you happy.