VoIP Validator: How to Tell if a Business Number Is VoIP Before You Call

More and more local businesses answer the phone through an app, a call-forwarding service or a cloud phone system. Those numbers are VoIP (voice over internet). A VoIP validator tells you which numbers on your list are VoIP, which are landlines and which are mobiles, so you know who will pick up and how to reach them.

What a VoIP validator actually checks

A good VoIP validator does not call the number. It looks the number up in carrier and numbering data and returns:

• Valid or not: is the number assigned and reachable on the network?
• Line type: VoIP, landline (fixed), mobile or toll-free.
• Carrier: the company that runs the line (often a hint: a cloud phone provider means VoIP).
• Country and format: the number in a clean international format for your dialer.

Why so many small businesses use VoIP

• It is cheaper than a traditional business line.
• Calls ring on the owner's mobile, so a one-person business looks bigger.
• They can keep the same number when they move.
• Many website and Google Business Profile numbers are tracking or forwarding numbers, which are almost always VoIP.

How to call each line type

VoIP numbers

Often forwarded straight to the owner's phone, sometimes to a receptionist service. Call during business hours, introduce yourself quickly and ask for the owner by name. If a virtual receptionist answers, leave a short, specific message (see our voicemail script for cold calling).

Landlines

Usually the front desk. Ask for the owner or office manager, and call outside the busiest hours of that trade.

Mobile numbers

Very often the owner's own phone. Early mornings work well for trades. Be brief and respectful: you are calling someone's personal phone.

When a number comes back invalid

Remove it from your call list and look for another number: the business's Google listing, its Facebook page or its website footer. An invalid number on a business that is still open is also a selling point: their listings show a number nobody can reach.

Check numbers in bulk before a call session

1. Import or find your leads for the day.
2. Run the phone check on the numbers you have not checked yet.
3. Sort your list: mobiles first in the morning, VoIP and landlines during office hours.
4. Skip invalid numbers and fix them later.

For the difference between the two most common types, read how to check if a number is a landline or mobile.