Your other number is calling.

With patented technology, the Sideline app gives you a second phone number that’s just as reliable as your first.

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Call with confidence.

Sideline works with your existing carrier network (not VoIP) to deliver great call quality anywhere your phone has service.

See which number is ringing.

Custom caller ID makes it clear which number is ringing so it's easy to prioritize calls and answer accordingly.

Protect your privacy.

With your primary number separate, Sideline lets you stay safe and anonymous whenever you need to.

A second phone number—and so much more

Superior Call Quality
Superior Call Quality

Sideline uses your carrier’s network for top-tier call quality.

No WiFi Needed
No WiFi Needed

Unlike VoIP services, Sideline gives you the freedom to leave your WiFi network.

Avoid Spam
Avoid Spam

We detect spam calls, telemarketers, and potential fraud so you can easily avoid them.

Auto-Reply
Auto-Reply

Send an automated text reply to any missed calls or messages.

Voicemail
Separate Voicemail

Record your Sideline greeting so people can leave a message after the beep.

Unlimited Messaging
Unlimited Messaging

Send unlimited SMS, MMS, and group messages.

Number Porting
Number Porting

Already have a second number? Bring it to Sideline from another device or landline.

Ring and Text Tones
Ring & Text Tones

Differentiate between numbers with unique ring and text tones.

Get started with Sideline today.

Start your free 7-day trial on iOS or Android.

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