Your phone's other number.

Sideline’s patented technology ensures that your second number works just like your first.

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

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

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

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

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

Get a second phone line for calls, texts, voicemail, and more.

Sideline detects spam calls, telemarketers, and potential fraud so you can easily avoid them.

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

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

Send unlimited SMS, MMS, and group messages.

Take the conversation to a bigger keyboard with the web texting portal.

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

Differentiate between numbers with unique ring and text tones.

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