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.
With patented technology, the Sideline app gives you a second phone number that’s just as reliable as your first.
Get Started for FreeCall 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
Sideline uses your carrier’s network for top-tier call quality.
No WiFi Needed
Unlike VoIP services, Sideline gives you the freedom to leave your WiFi network.
Avoid Spam
We detect spam calls, telemarketers, and potential fraud so you can easily avoid them.
Auto-Reply
Send an automated text reply to any missed calls or messages.
Separate Voicemail
Record your Sideline greeting so people can leave a message after the beep.
Unlimited Messaging
Send unlimited SMS, MMS, and group messages.
Number Porting
Already have a second number? Bring it to Sideline from another device or landline.
Ring & Text Tones
Differentiate between numbers with unique ring and text tones.