AI phone numbers: what they are and how to get one

An AI phone number picks up your business calls, talks to the caller, and handles things like taking messages, answering questions, booking appointments, and routing calls to the right person. All without you or your staff touching the phone.

So instead of a customer calling your plumbing company at 8pm and hitting voicemail, the AI answers, asks what they need, collects their info, and texts you a summary. You wake up to a lead instead of a missed call.

Here's what AI phone numbers are, how they actually work, and how to set one up for your business in about 10 minutes.

What AI phone numbers actually are

An AI phone number is a regular business phone number with an AI voice agent behind it. The caller dials in, hears a real-sounding voice, and has a conversation, just like they would with a receptionist.

The difference: this receptionist works 24/7, never calls in sick, and handles five calls at once without putting anyone on hold.

Under the hood, the AI uses voice recognition to hear what the caller says, natural language processing to understand what they mean, and machine learning to get better at it over time. But you don't need to know any of that to use one. Think of it like a GPS. You don't need to understand satellite triangulation. You just type in the address and go.

One law firm owner we talked to said it well: "Our phones are our lifeblood, the very most important thing." For most service businesses, that's true. And yet most of those calls still go to voicemail after 5pm.

How it works in practice

Here's what the setup looks like for most businesses:

1. You pick a provider (more on this below).

2. You tell the AI what your business does, what questions callers typically ask, and how you want calls handled.

3. You forward your existing business number to the AI phone number, either all the time or just when you're busy or after hours.

That's it. You don't need new hardware, an IT person, or a different phone carrier.

When a call comes in, the AI:

• Greets the caller with your business name
• Asks what they need
• Answers common questions (pricing, hours, services)
• Books appointments if you've connected a calendar
• Takes a message and texts or emails it to you
• Transfers the call to a live person if it's urgent

Most callers don't realize they're talking to an AI. And even when they do, they don't care, because they got their question answered in 30 seconds instead of leaving a voicemail and waiting two days.

AI phone numbers vs. traditional phone systems

The cost difference is the one that gets people's attention. A full-time receptionist runs $30,000-45,000/year. A traditional answering service costs $1,500-3,000/month. Most AI phone numbers cost less than your internet bill.

Why businesses are switching

Every call gets answered

An insurance broker told us the main thing he wanted was to "catch anybody after hours, instead of going to just our voicemail." That's the number one reason businesses switch. The AI picks up every call, day or night, so callers never hit voicemail or play phone tag.

You stop being the receptionist

We've talked to solo attorneys who say "I'm the receptionist" like it's a confession. They went to law school to practice law, not answer phones. AI phone numbers handle the routine stuff, like "what are your hours" and "do you handle car accidents," so you can do the work you actually get paid for.

You get a summary after every call

Instead of checking voicemail (if the caller even left one), you get a text or email after each call with the caller's name, what they needed, and whether it's urgent. It's like having a receptionist who takes perfect notes every time.

It scales without you hiring anyone

Busy season hits. A marketing campaign drives a spike in calls. Instead of scrambling to hire temp staff, the AI just handles it. One landscaping business owner told us he manually batches jobs by geography to maximize his time. AI phone numbers do that kind of smart call routing automatically.

What AI phone numbers can't do (yet)

Worth being honest about the limitations:

• Highly emotional or complex conversations are still better handled by a person. The good news: most providers let you set up call transfers for situations the AI can't handle well.
• You need to spend an hour or two on setup. Writing your greeting, defining call flows, and adding your FAQs takes some thought. It's not hard, but it's not zero effort either.
• It occasionally gets things wrong on unusual calls. Heavy accents, loud background noise, or very niche questions can trip it up. Good providers let you review transcripts and fine-tune responses over time.

None of these are dealbreakers for most businesses. But it's worth knowing what you're working with.

How to set up an AI phone number

Three steps. You can do this over a lunch break.

1. Pick a provider

Not all AI phone numbers are built for the same audience. Here's a quick comparison:

The main question to ask yourself: can you set it up without a developer? If the answer needs to be "yes," look at Upfirst or Goodcall. If you have a dev team, Bland AI and Retell AI give you more control.

2. Configure your AI

Once you've picked a provider:

• Write a short greeting. Something like: "Hi, thanks for calling [Business Name]. How can I help you today?"
• Add your FAQs. What do callers ask most often? Pricing, hours, service areas, how to book. Put those in.
• Set up call flows. Decide what happens for different scenarios. New lead? Take their info. Emergency? Transfer to your cell. Spam? Hang up.
• Connect your tools. Link your calendar for appointment scheduling, your CRM for lead capture, or Zapier for custom workflows.
• Test it. Call your AI number from your personal phone. Try a few different scenarios. Tweak the script based on what you hear.

3. Forward your calls

You don't need to give out a new number. Just set up call forwarding from your existing business line to your AI phone number.

You can forward all calls, or only forward when you're busy, on another call, or after business hours. Most carriers support this with a quick settings change on your phone.

A quick note on compliance

The FCC ruled in February 2024 that AI-generated voices in phone calls fall under the Telephone Consumer Protection Act (TCPA). Here's what that means in plain English:

• Answering inbound calls with AI is fine. The customer called you. You're in the clear.
• Making outbound AI calls requires consent. Same rules as robocalls. You need prior express consent.
• Being upfront about AI builds trust. Letting callers know they're speaking with an AI isn't just good practice, it's good business.

If you're a small business using an AI phone number to answer inbound calls, you don't need to worry. This mostly affects companies doing outbound AI calling at scale.

Frequently asked questions

Is AI calling illegal?

No. Answering inbound calls with AI is legal. Outbound AI calls require consent under the TCPA, same as any automated call.

Can I keep my existing phone number?

Yes. You forward your current number to the AI phone number. Your customers never see a change. Most providers also support number porting if you want to transfer the number entirely.

How much does an AI phone number cost?

Most small businesses pay $25-100/month. That's a fraction of what a traditional answering service costs ($1,500-3,000/month).

Can it handle multiple calls at once?

Yes. Unlike a person, an AI phone number handles several simultaneous calls without putting anyone on hold or sending anyone to voicemail.

What if the AI can't answer a question?

It transfers the call to you or another team member. You set the rules for when that happens, like always transferring emergency calls or calls from VIP clients.

Try it yourself

If you're still picking up every call yourself, or worse, letting them go to voicemail, an AI phone number is the fastest fix.

Upfirst takes about 10 minutes to set up. It answers your calls 24/7 and sends you call summaries after every conversation, so you always know who called and what they needed.

Try Upfirst free and see how it works for your business.