They Asked for My Cell Number. I Don’t Have One.
What to do if you're asked for your cell number, and you don't want to hand it over.
I just tried to set up a new account, and it asked for my phone number.
Not a VoIP number. It demanded a real SIM-based cell number.
The problem is that I don’t have a SIM in my phone. Which means that I actually don’t have a cell number, the number associated with a SIM.
What should someone do in a situation like this?
Now I know I’m an anomaly here. Most people DO have a cell number.
But there are plenty of reasons someone might decide not to hand out their cell number every time a company asks. Here are two:
One big reason is that we end up giving out the same cell number to everyone. Thousands of merchants, restaurants, our doctor, school, the government, work colleagues. It becomes a unique identifier tying all our activities together. Almost every service you use shares data about you, and that data makes its way to data brokers. With the same cell number linking every account that you use, data brokers can now see everything you’re doing. So can criminals on the dark web: all of this data ends up in dark web breaches too. Anyone digging through those data dumps can tie your scattered accounts together and piece together an intimate picture of your life.
Cell numbers are tied to the telecom network in a way that creates an additional privacy risk. Cellular networks keep track of where your phone is so they can route calls and texts. That is part of how the system works. Cell numbers record your location in what’s known as a Home Location Registry, and this becomes a map of everywhere you’ve been. Telecom providers are notorious for selling your location data. Unlike cell numbers, VoIP numbers don’t actually get logged in the HLR, so it’s much safer to give someone a VoIP number than a cell number.
In this newsletter, I’ll walk through a few scenarios where you might be asked for your number, and how to avoid giving up your SIM-based identity.
1. In Person: my default line
If someone in person asks for my number, and I know it’s not actually necessary, I tell them:
“I don’t currently have a working number.”
Here’s what I’ve learned after doing this for years.
If you say “I don’t have a phone” or “I don’t have a number,” people often don’t believe you, or they get hostile. You get the “well you need one to enter in our system” pushback.
But “I don’t CURRENTLY have a working number” sounds like your phone broke or you are between plans. It gives them a socially acceptable reason to move on. If you are polite and even a little apologetic, they often waive the requirement.
2. Online: VoIP is the best default
If you are dealing with businesses online, they often force you to enter a number.
For important accounts, you can get up to 9 VoIP numbers using MySudo, where you can receive SMS and calls just like cell numbers (GrapheneOS users will have trouble getting calls in real time, but can receive voice mail fine). You can keep those numbers as long as you keep paying for your plan.
For important numbers, I have different numbers I use for different purposes: Work, friends, shopping, medical, etc.
If you want to generate a new number for every service you use, you can get hundreds of VoIP numbers using Cloaked.com.
I do this for all burner accounts, restaurant reservations, one-time purchases, etc.
VoIP numbers will almost always work. But there are some entities that don’t accept them. Let’s go over what to do in those situations.
3. If VoIP is rejected and the account is not important
If VoIP is rejected and you need a SIM-based number for a low importance account, some people use temporary number rental services.
Smspool.net is one option you can use: You deposit money in your account, and can rent a number cheaply just to receive a one-time code. You can also pay in cryptocurrency, including many privacy coins, which is super convenient.
Some platforms require a number when you first register your account, but afterwards you can go into your settings and change the number to anything, including VoIP. If that’s the case, you can rent a temporary number just for sign up, and then go into your new account and switch the number out.
There are other services that demand SMS verification every time you sign in, and if you lose access to this number you will lose access to your account. If this is the case, you don’t want to put a temporary number.
One tip is to rent a number for at least an hour: This gives you a little more time to see if this account is going to require this number for ongoing identification each time you use the account, and whether you’ll be blocked from your account if you lose access to your number. If you do require ongoing use of a number, you can rent a number long term, but that can get pricey. I recommend a more permanent solution, so let’s talk other options.
4. If you need a number long term: keep a dedicated SIM you control
If you need to provide a SIM-based number on an ongoing basis, you can buy a prepaid SIM. Just make sure that you maintain access to it. That means keeping it active so you do not lose the number, and being sure to top it up when needed. You can also use services like Bitrefill to top up your prepaid SIM.
Then whenever a company insists on a “real” cell number, you have one. But it is not the same number you give to everyone.
Why some providers block VoIP:
As mentioned, sometimes services reject VoIP numbers, and ask for a “real” cell number. This usually happens for one of two reasons:
1. The sender blocks VoIP numbers for KYC reasons.
This isn’t a usually a technical limitation, they do this because SIM-based numbers are generally better to KYC someone. Some banks and websites check whether your number is classified as a cell-based number or a VoIP number, and they simply block you if the number is classified as VoIP. They just don’t like VoIP.
2. The sender blocks VoIP numbers for fear of compatibility issues.
Some VoIP providers don’t support short code delivery. Short codes, like 5 digit verification codes, actually aren’t like normal SMS:
Think of your phone number like a mailbox, and texting like mail delivery. Most texts are “regular mail” that almost any mailbox can receive. But short code texts are more like a special kind of delivery service that uses different routes and rules than regular SMS. Behind the scenes, phone service is not one single thing. Providers turn on different capabilities depending on how a number is set up. Short codes are one of these capabilities you can switch on or off.
With VoIP numbers, the provider that issued the number (and the upstream carrier they route messages through) may simply not support short code routing for that number type. So even if your VoIP number can receive standard texts, it might not be provisioned with the right carrier connectivity to accept short code messages.
Because there’s a chance some VoIP numbers might not work with a company’s messaging system, they might decide to simply block all VoIP numbers.
The Cell to VoIP Trick (with caveats)
Sometimes a company checks your number at registration to confirm it is a cell number, but after that, they never check again. In those cases, one approach is to use a SIM based number initially, then later port that number to a VoIP provider (like MySudo). You will continue to get access to that number, but now it’s cheaper to maintain, and the VoIP number isn’t being logged in any HLR.
But there is a caveat: as mentioned, some VoIP numbers can’t receive short codes. So after a number becomes VoIP, you may stop receiving some verification codes. This is something you have to test. You do not want to be stuck unable to receive SMS codes when you need to log in.
In my experience, most codes reach VoIP numbers.
Maybe 5% of the time, I can’t get codes, but they give me a call option instead, which works just as well.
But occasionally, a specific short code just will not deliver to a particular VoIP setup. If that happens, you may need to try a different VoIP provider, or keep a SIM based number for that specific account.
The bigger point
Data collection today is normalized and invasive. Everyone wants your home address, your phone number, your social accounts, and every identifier that makes it easier to map your life and sell it.
You do not have to make it easy for them.
In the digital era, “just type your number” is treated like a harmless formality.
But it’s not harmless. Every extra identifier makes it easier to map your life.
So let’s stop volunteering this information, and let’s instead make it normal to push back. Where we can, let’s opt to give companies what they need to provide the service, and nothing more.
Yours In Privacy,
Naomi
**As always, this newsletter was not sponsored. These are just tools that I personally use and like. If you have tools that you recommend people try out, let them know in the comments!
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