Many of the big email service providers now require a mobile phone number in order to create an account (a land line isn't acceptable). My understanding is that mobile phone access is used to activate the account (possibly via SMS messaging of a PIN?).

I live in a cell tower hole and get no signal in the vicinity of my house. So I haven't bothered with a cell phone. I'm also in need of a new email provider for the first time in many years, so it's the first time I'm running into the cell phone hurdle, and I'm a bit hazy on the requirements.

My read is that the requirement is a mobile phone number with the ability to receive SMS messages.


Is it possible to emulate this on a computer? For example, there are VOIP services that will provide a phone number, and apps for exchanging SMS messages. Can I cobble something together that would appear to the email provider to be a cell phone, which would be adequate to receive a text message to authenticate a new account?

Or is a separate device part of the security design, so nothing you do on the computer would work? I know that the email account creation includes identifying whether the phone number is a land line or mobile number; I'm not familiar with whether VOIP phone numbers are a third identifiable class.

If it makes a difference, I mainly use Linux, but can still access Windows 7.

  • What country are you looking for service in? Not sure if you are aware that you generally only need the phone for SMS for initial validation, so you can probably do this from a prepay/burner phone away from your computer. (Or, if its an option in your country, buy a sim card and use it in someone elses phone for setup - just check that, after validation, there are methods of validation other then cellphone in case it gets lost) VOIP phone numbers are not inherently identifiable as such, but the issues are more likely to be around SMS signalling... – davidgo Mar 6 at 6:11
  • I don't know any VOIP providers who provide SMS, but its probable they exist somewhere. – davidgo Mar 6 at 6:11
  • @davidgo, I'm in the US. The requirement is only for account creation. I own a cell phone, but there's no signal. There is generally a time limit for entering the PIN, so it wouldn't be practical to get to where I can receive a message and then get back to the computer to enter it (unless it works by replying on the cell phone). re: phone numbers, they distinguish between land line (no SMS) and cellular numbers. Any idea which category VOIP numbers fall in? – fixer1234 Mar 6 at 6:31
  • Why not do the whole initial setup on your cellphone, then go back and add your computer? – davidgo Mar 6 at 6:41
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    Many VOIP services are capable of SMS. For those which are capable, a regular cell phone can exchange SMS with the VOIP phone. Computer to SMS, however is more complex as the computer has to use a gateway into the cell provider's system to send the SMS to a cell phone. Most VOIP providers have no such gateway (API) which eliminates that option for the OP. I do wish I remembered which one it was, but I was able to "validate" for some email provider using SMS on my VOIP (MagicJack) phone. It might have been Gmail, but I don't think so. – Gypsy Spellweaver Mar 6 at 7:45

Usually the verification of number ownership is SMS-based (requiring a mobile phone). But if the email provider allows you to select "fixed/landline" as an option, that means they'll deliver the verification code through an (automated) voice call instead. That's the only reason they need to know the phone type.

So if your VoIP line can receive SMS messages it can safely count as 'mobile', if it's voice-only choose 'landline'. (Google/Gmail supports both. Other providers tend to use cheaper SMS-only services.)

For many providers this is an anti-spam measure, not a security measure – that is, they rate-limit the number of accounts that a single phone number may verify in a short amount of time. (Google support: "we will sometimes ask you to prove you’re not a robot […] In an effort to protect you from abuse, we limit the number of accounts each phone number can create.")

So I wouldn't be surprised if they deliberately blacklisted the most popular VoIP services. But on the other hand, it means you'll only need to receive a code once (during signup).

  • Interesting. I'm avoiding Gmail. Most of the other providers are SMS only. Is there a mechanism for them to ID an SMS-capable number, or is acceptability determined by just whether it's a land line or cellular number? It sounds like I need to investigate VOIP services to see if any offer SMS (and find an app that does it with VOIP), and then see if it passes muster with an email provider. – fixer1234 Mar 6 at 6:43
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    The method used for a website, or anyone else, to determine the mobile/landline (VOIP) status is to check what block of numbers the given number is in, and who owns that block. If the block owner has an SMS API it might be a mobile, and the API can be queried for the ability to send SMS to that number. In countries where number portability has been enabled (or enforced) the system has a database to correct for cross-provider transfers, adding a step to the process, with the same end results. – Gypsy Spellweaver Mar 6 at 7:52

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