2Line.AI or Sideline?
Sideline gives you a second number for calls and texts on your phone, from $14.49 a month. 2Line.AI does that too, and adds Mia, an AI receptionist who answers missed calls, books appointments and sends follow-up texts.
| 2Line.AI | Sideline | |
|---|---|---|
| Price | $19.99/month, or $99.99/year with 3 days free. One plan, plus credits for calls, texts and Mia (see the pricing page). | $14.49 a month, or $129.99 a year. |
| AI receptionist | Yes, Mia | Not listed |
| Appointment booking | Yes, inside your business hours | Not listed |
| Missed-call text back | Yes | Not listed on the pricing page |
2Line.AI credit rates for calls, texts and Mia are on the pricing page. Competitor details checked on their own websites on October 26, 2026. Prices change, so check their site before you decide. Sources: Sideline: how much does it cost (support.sideline.com).
Who each is for
Sideline is for people who want a second number for calls and texts and plan to answer it themselves. It’s a straightforward second line at $14.49 a month or $129.99 a year. If your calls are easy to pick up, or you’d rather call everyone back personally, a simple second-number app may be all you need.
2Line.AI is for owners who also need help with the calls they can’t take. It’s a second number too, and you can switch Mia off and use it just that way. When she’s on, she answers in your business name, books appointments inside your hours, sends the caller a “what happens next” text and leaves you a slip, and the line sends reminders and review requests after the job.
What a typical day looks like with each
With Sideline
You run a cleaning business and spend the morning in a client’s home. Three calls come in to your second number while your hands are full. With an app built for calls and texts, each one waits as a missed call until your break. Then you call them back in the order you see them, hoping they haven’t booked someone else in the meantime.
With 2Line.AI
With 2Line.AI, Mia takes the calls. One caller wants a price, so she texts a quote from the prices you gave her, and they can reply YES to accept. Another books a Thursday clean inside your hours. The third was labelled likely spam before it rang. At your break you read two slips and see one new booking, instead of returning three calls.
Choose 2Line.AI if
- You want the line to answer and book for you
Sideline may fit better if
- You only need a second number and plan to answer every call yourself
Switching from Sideline to 2Line.AI
- Pick a new local number in 2Line.AI from the area codes near you. Porting isn’t supported, so this is a new number, not your Sideline number moved over.
- Set your business name, hours and caller ID name (up to 15 characters). Teach Mia from your business name or website, then call the new number from another phone to test her.
- Keep Sideline running while you switch, so anyone who still has the old number reaches you. A month or two of overlap is a sensible minimum.
- Tell your customers. Text your regulars from the new number, and change the old number’s voicemail greeting to give the new one.
- Update your Google Business Profile (Edit profile, then Contact, then Phone number), then your website, Apple Maps, Yelp, Facebook, cards and truck.
- When calls to the old number have slowed to a trickle, cancel Sideline.
Because both apps put a second number on the phone you already have, you can run them side by side during the overlap and answer whichever one rings. Step-by-step help for Google is in our guide to changing your Google Business Profile phone number.
What 2Line.AI doesn’t do
Worth knowing before you choose:
- No number porting. You get a new local US number; you can’t move an existing number in.
- No international numbers or calling. Numbers are US only, for calling and texting US numbers.
- Calls, texts and Mia aren’t bundled into the plan; they use credits. At zero credits they pause until you add more, and your number stays yours.
- No shared team inbox or per-user seats. Each account has one owner, with as many lines as you need.
- No 911 calls. Keep your regular phone for emergencies.
Questions
Can I use 2Line.AI just as a second number?
Is 2Line.AI more expensive than Sideline?
Does Sideline have an AI receptionist?
Does 2Line.AI need a second phone?
Can I try 2Line.AI before paying?
How much does 2Line.AI cost?
Other comparisons
A Sideline alternative that answers for you.
Yearly comes with 3 days free. $19.99 a month or $99.99 a year.
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