Carrying two phones so you can keep work calls separate from personal ones is a hassle nobody actually wants. The good news is you don’t need a second device at all — a VoIP (voice over internet) app can give your existing smartphone a completely separate business number, with its own voicemail, texting, and caller ID, running right alongside your personal line.
Table of Contents
This guide walks through how these apps work, the main options worth considering, what they cost, and the setup steps so you can have a working business number in about 15 minutes.
Quick Answer
Download a VoIP business phone app (Google Voice, OpenPhone/Quo, or Grasshopper are the most popular), choose a local or toll-free number, and the app adds a second line to your existing phone that works over Wi-Fi or data. No new SIM card, no second device, and no carrier contract required.
How It Actually Works
These apps don’t touch your carrier’s SIM at all — they route business calls and texts over the internet instead of a traditional cell network. The app runs like any other app on your phone, but incoming calls to your business number ring through it with a distinct sound and caller ID, so you always know whether a call is business or personal before you answer.
Because everything runs over data or Wi-Fi, the same number and app also work on a laptop or tablet, which is useful if you want to answer business calls from a desktop when you’re at your workspace.
One thing to plan for: business text messaging in the US runs through a carrier system called A2P 10DLC, administered by The Campaign Registry on behalf of the major carriers (not a government agency). Your provider will typically walk you through registering your business, and this generally means a paid business plan — rather than a free consumer tier — is required if you intend to text customers regularly.
The Main Options and What They Cost
Google Voice is the simplest entry point. It has a free personal tier, but that’s not meant for business use and doesn’t support business texting. For a real business number, Google Voice’s paid Starter plan runs about $10 per user/month, Standard (adds an auto-attendant/call menu) is about $20/month, and Premier is about $30/month. If your business doesn’t already have Google Workspace, budget for that too — plans start around $7-8/user/month, pushing the realistic minimum closer to $17/month.
OpenPhone, recently rebranded to Quo, is built specifically for small teams that want a dedicated second number without enterprise complexity. Its Starter plan is about $19/month billed monthly (around $15/month billed annually) and includes one number, unlimited US/Canada calling and texting, and voicemail transcription. The Business tier (around $33/month monthly, $23/month annual) adds call recording, AI call summaries, and CRM integrations like HubSpot and Salesforce. Extra numbers run about $5/month each.
Grasshopper takes a flat-rate approach aimed at solo operators and small teams: plans start around $14/month (annual billing) for a single line, with higher tiers adding more extensions and unlimited users at a fixed price rather than per-seat pricing — useful if several people need to share one business number.
To set one up: pick an app, choose a local or toll-free number (most let you search by area code), verify your identity and existing phone number, complete any carrier registration the app requires for texting, set up your voicemail greeting and business hours, and you’re taking calls within minutes.
Tips and Common Mistakes
Don’t rely on the free consumer tier of any of these tools for real business use — beyond the texting compliance issue, free tiers typically limit you to one user and offer no support if something breaks. Also check whether a plan is billed monthly or annually before comparing prices; the annual rate is often noticeably cheaper per month, but it locks you into an upfront payment.
If you’ll have more than one person answering the business line, look closely at whether pricing is per-user (Google Voice, OpenPhone) or flat-rate for unlimited users (Grasshopper) — that difference adds up fast as a team grows. Finally, confirm the app supports both calling and texting on the number you choose; toll-free numbers sometimes have different texting rules and registration steps than local 10-digit numbers.
Explore more: More small business tech guides.
Business phone number apps FAQs
Do I need a new SIM card to get a business phone number?
No. VoIP business phone apps run over Wi-Fi or your existing data connection, so your current SIM and carrier plan stay exactly as they are.
Can I use a free app for my business number?
Free consumer tiers (like the free version of Google Voice) aren’t intended for business use, typically don’t support the carrier registration needed for business texting, and often limit you to a single user — a paid plan is the safer choice.
What is A2P 10DLC and do I need to worry about it?
A2P 10DLC is a carrier-run registration system (managed by The Campaign Registry, not the FCC) that businesses must complete to send text messages reliably from a standard 10-digit number. Most business phone apps handle the registration process for you as part of signing up for a paid plan.
Can more than one employee answer the same business number?
Yes — most of these apps support shared numbers so multiple team members can see and respond to the same business line, though pricing models differ (per-user vs. flat-rate) so check which fits your team size.
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