The short answer
If the number is just for you — marketplace listings, dating apps, sign-up forms — get a free app number and stop reading. If you are going to hand the number to customers, skip the carrier (roughly $35–$50 a month for a line you do not need) and get a business line inside an app instead. That runs about $10–$15 a month all in, works on the phone in your pocket, and is the only option that can give you a toll-free number.
Why people end up wanting a second number
Almost nobody goes looking for a second phone number on a good day. It usually starts with a specific moment: a customer calls at 9pm on a Sunday, or a stranger from a marketplace listing now has the number your kids' school uses, or you realise every invoice you have ever sent has your personal mobile printed on it.
The reasons cluster into three groups, and which group you are in decides which option below is right for you.
- Privacy. You want a number you can hand out freely without giving away the one your family calls.
- Separation. Work and life are bleeding into each other and you want to be able to switch one of them off.
- Looking established. You are running a business from a personal mobile and it shows — especially when the caller ID is just a bare number.
The first two you can solve for free. The third you cannot, and that is the honest dividing line running through this whole guide.
The four ways to get one
Every method you will read about anywhere is a version of one of these four. Each card below gives you the same four facts so you can compare them honestly — including the catch, which is the part most articles leave out.
Add a line to your carrier plan
You call Verizon, AT&T or T-Mobile and add a second line to your existing account. They send you a SIM (or activate an eSIM), and you get a second number with its own calls, texts and data allowance.
The catch: you are buying a whole second cell plan — data, allowances, the lot — when all you actually wanted was a second number. It is the most expensive answer to the question by a wide margin, and it still cannot give you a toll-free number or business features like call recording.
Use dual SIM or an eSIM
Most phones sold in the last few years can hold two lines at once — one physical SIM and one eSIM, or two eSIMs. You keep your existing plan on one and put a second, usually cheap prepaid, plan on the other. Both numbers ring the same handset.
The catch: dual SIM is a way to carry two carriers, not a way to get a business line. It is genuinely excellent if you travel or want a cheap second plan — but you still end up paying a carrier monthly, your phone has to support it, and you get none of the things a business number needs.
Get a free second-number app
Apps like Google Voice and TextNow hand you a second number that works over the internet, on the phone you already have, at no charge. For personal use this is genuinely the right answer and we will not pretend otherwise.
The catch: free tiers are built for personal use, and the limits show up exactly when a business needs them not to. Google Voice's free personal tier, for example, issues local numbers only — no 800-style toll-free — generally needs an existing US phone number to sign up with, has no call recording, and numbers can be reclaimed after long periods of inactivity. There is also no one to call when something breaks.
Get a business line inside an app
This is a real phone line from a phone company, delivered through an app on your existing phone rather than a SIM. You pick the number — any available local area code, or a toll-free 800, 833, 844, 855, 866, 877 or 888 — and it rings alongside your personal line with its own texts and voicemail.
The catch: it is not free, and if the number really is just for marketplace listings you are paying for capability you will never use. What you get for the money is the business half: your choice of number including toll-free, custom caller ID so your business name shows instead of a bare number, call recording, spam and robocall blocking, auto-reply texts, and a company that answers the phone.
Side-by-side comparison
| Option | Typical monthly cost | What you need | Toll-free? | Best for |
|---|---|---|---|---|
| Add a line to your carrier plan | ~$35–$50/mo, plus taxes and fees | Same phone (needs dual SIM or eSIM) or a second handset | No | Someone who wants a full second cell plan with its own data |
| Dual SIM / eSIM | Cost of whatever plan you put on it | Same phone, if it supports two lines | No | Travellers and anyone who needs a second carrier, not just a second number |
| A free second-number app | Free (ad-supported or feature-limited) | Same phone | No | Personal use — marketplace listings, dating, sign-up forms |
| A business line in an app | About $10–$15/mo all in | Same phone | Yes | Anyone giving the number to customers |
Carrier and app pricing changes constantly — the figures above are a 2026 snapshot and worth confirming on each provider's own pricing page before you commit.
Which one is right for you
Find the sentence that sounds like your situation.
“I just don't want strangers to have my real number.”
Use a free app. You are not going to use the business features, so do not pay for them.
“I travel, or I want a cheaper second carrier.”
Dual SIM or eSIM. This is the one problem a second carrier line actually solves better
than an app.
“I'm running a business off my personal mobile.”
A business line in an app. It is the only option that gives you a toll-free number,
a business name on caller ID, and call recording — for a fraction of what a
carrier charges to add a line.
“I need a second line for a whole team.”
None of the above on its own — look at a multi-user business phone plan, where
numbers, extensions and call routing are managed together.
How to set one up in about five minutes
This walkthrough is for the business-line route, because it is the one people get stuck on. Here it is with our own Second Line plan, which is $9.99 a month for one person and one number — but the steps are much the same wherever you buy.
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Decide local or toll-free
A local area code makes you look like a neighbour, which is what you want if your customers are nearby. A toll-free number makes you look established and national. Pick on how you want to be seen — both cost the same.
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Search for the number itself
You choose the actual number, not whatever gets assigned to you. Try your area code, or search for a word that spells out on the keypad if you want something memorable.
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Check out
Email, phone verification, payment. Expect to see the federal Universal Service Fund fee and state sales tax on top of the plan price — every US phone line carries these, and any provider quoting you a plan price alone is quoting you an incomplete number. Ours works out to $13.06 a month all in.
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Install the app and sign in
Your new number lives in the app on the phone you already carry. No second SIM, no second handset, nothing to install on another device.
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Set it up before you hand it out
Ten minutes now saves you a month of annoyance: record a voicemail greeting, write the auto-reply text for when you are busy, set your business name as the caller ID, and give the line its own ringtone so you know which hat to wear before you answer.
Five mistakes worth avoiding
- Comparing plan prices instead of all-in prices. Every US phone line carries the federal Universal Service Fund fee and state tax. A $9.99 plan and a $9.99 plan can land differently on the card — ask what the total is.
- Handing out the number before you set up voicemail. The first impression of your new business number should not be a robot reading digits back.
- Using a free personal number for business texting. Free consumer tiers are not built or licensed for it, and it is a bad place to discover that.
- Picking a toll-free number when your customers are local. If you serve one town, a local area code converts better. Toll-free is for reach, not for prestige alone.
- Not turning it off. The whole point of a second line is that you can silence it at 6pm. If you never do, you have bought a second number and kept the same problem.
Questions people actually ask
Yes. You can do it with a second SIM or eSIM if your phone supports two lines, or with an app that adds a second number over the internet. The app route is the more common one now because it does not require a second plan from a carrier.
A free app like Google Voice costs nothing if you only need a basic personal line, you already have a US phone number to verify with, and you can live without toll-free numbers, call recording and support. If you want the number for a business, a paid second line usually runs about $10 to $15 a month — far less than the $35 to $50 a carrier typically charges to add a line.
No. Every option except a second physical SIM in a second handset runs on the phone you already carry. An app-based second number puts both lines on one device with separate ringtones, separate texts and separate voicemail.
Only from a phone service provider. Free consumer apps issue local numbers only — Google Voice, for example, does not offer 800-style toll-free numbers. If you want customers to see an 800, 833, 844, 855, 866, 877 or 888 number, you need a business line.
Not from the call. Outgoing calls and texts show the second number you chose, and your personal number is never displayed. What gives it away is usually behaviour, not technology — answering business calls at midnight tells people more than your number ever will.
With an app-based or business line, yes — the number belongs to your account, not the handset, so you sign in on the new phone and carry on. With a carrier line or a physical SIM, the number moves with the SIM or has to be ported.
The plan is $9.99 a month with no setup fee. Like every phone line in the US it also carries the federal Universal Service Fund fee ($2.25) and state sales tax ($0.82), so the card is charged $13.06 a month. Unlimited calling is included and you can cancel anytime.
Two small moves this week
First, decide which of the three groups you are in — privacy, separation, or looking established. That single answer eliminates three of the four options above and saves you the comparison-shopping spiral entirely.
Second, if you landed on the business-line answer, go and search for the number before you think about providers. Finding out what is actually available in your area code takes two minutes and makes the decision concrete. You can do that on our Second Line page — $9.99 a month, one number, on the phone you already own.