How to mask your number to protect your privacy?

4 August 2025 | 6 mins read

A person wearing a white mask holding a smartphone with an unlocked screen.

Between us… You care about your privacy, right? 😎 So let me share with you some tips to ensure your number doesn't become the star of marketing files. More specifically, how to keep your phone number to yourself, away from prying eyes. Gone are the days when your number roamed free like a celebrity without bodyguards! 🕵️‍♂️ Let’s dive into the world of masked numbers!

🤫 How to mask your number to protect your privacy? The ultimate guide!

As you know today, we live in a hyperconnected world… Well, that's great, but it also has its downsides. Our personal information, especially our phone number, has become a true currency. According to a recent study, over 53% of web traffic comes from mobile devices, highlighting how central our smartphones are to our lives. It is therefore more important than ever to know how to mask your number.

Whether you want to avoid harassment, protect yourself during online sales, or simply maintain a clear separation between your professional and personal life, hiding your phone number is an essential skill to master. And the good news? It’s super simple!

✨ The art of temporary masked calls: The famous #31#

This is the basic technique, the foundation of incognito calling. Do you have just one call to make without revealing your precious number? No worries, the solution is also very simple..

A young man in animated style wearing a white mask and a grey hoodie, looking at his phone in an outdoor market.

The magic code: #31#

Imagine: you need to call a somewhat persistent customer service, or respond to an online ad without wanting to be called back at odd hours. That’s where the prefix #31# will come in handy.

How does it actually work? It's a piece of cake!

Grab your phone (it'll be better with 😅)
Dial #31# followed, without spaces, by the phone number you want to contact.
For example, to call 0612345678, you would dial:#31#
Make the call, and that's it! ✨

Your recipient will see "Private Number", "Unknown", or "Blocked Call" displayed on their screen. It's quick, efficient, and completely free. It works on all smartphones, whether you're on Team Android or a die-hard iPhone fan, and with any carrier.

Anecdote: I’ve lost count of the times I’ve pulled pranks on my friends or parents by calling from a blocked number, using an app that changes my voice 😂

It's the perfect solution for occasional needs, but be careful, you have to remember each time. One slip-up, and your number shows up! If you're looking for a more "permanent" solution, keep reading, the next part should interest you.

🥷 Go into ninja mode: permanently hide your number.

Are you tired of dialing #31# every time? Do you want ALL your calls to be private numbers by default? It’s entirely possible, and it’s done directly in your smartphone settings.

A young man in animated style wearing a white mask and a grey hoodie, looks at the camera while holding a smartphone in a crowded street.

📱 How to call from a blocked number on Android?

The steps may vary slightly depending on your phone brand (Samsung, Xiaomi, Google Pixel, etc.), but the principle remains the same. Generally speaking:

Open the Phone app.
Tap on the three little dots at the top right to access the Settings.
Look for an option like "Phone Accounts", "Call Settings" or "Additional Services".
Find the line "Show my Caller ID" or "Caller Identity".
Select Hide Number. And there you go, you're all set!

From now on, all your outgoing calls will be anonymous. No more stress! 😎

📱 How to hide your number on iPhone?

With Apple, it's even simpler, hiding your phone number is even more straightforward:

Go to your Settings on your iPhone
Scroll down and tap on Phone.
Select Show My Caller ID.
Simply turn off the switch.

When it’s gray, it means you’re in masked number mode. Easy, right?

Quick comparison of anonymous SMS sending solutions

Method	Advantages	Disadvantages
#31# (one-time)	Fast, simple, universal	Must be repeated for each call
Settings (permanent)	"Set it and forget it", constant protection	Can be a barrier to receiving calls

A friendly tip: If you mask your number permanently, remember to temporarily reactivate it if you’re expecting an important call and want the person to identify you. This will prevent you from ending up in blocked numbers!

🛡️ Alternatives: apps and services for customized privacy

Need to go even further? Maybe you have a professional activity that requires juggling multiple numbers, or you just want an extra layer of protection. I have solutions for you!

A man wearing a white mask, a dark jacket, and a blue t-shirt, is speaking into the receiver of an old-fashioned black phone, with a city street in the background.

Virtual number apps

Apps like our site Anonymous SMS, TextNow, or UnCall allow you to get a second phone number, often for free or at a low cost. It’s surely the best way to mask your main phone number.

Advantages:

Work/life separation:
Use one number for work and keep your personal number for your loved ones.
Online protection:
Sign up for websites or services without ever giving your real number
Flexibility:
Change your virtual number whenever you want

It’s like having a disguise for your phone! 🦸‍♂️

VoIP services (Voice over IP)

Services like Viber Out or TextNow also allow you to make calls to landlines and mobile numbers. By purchasing a bit of credit, you can call anywhere in the world, and your temporary number will show instead of your personal number.

A true story: I have a freelance friend who uses a virtual number for all his clients. This allows him not to be disturbed on weekends and to keep his personal number secret. Smart, right?

An important point to note: Using a private number is an excellent way to protect yourself. Many applications focus on the security and encryption of your communications, which is a real plus in our digital world.

🔎 The other side of the coin: managing blocked calls that you receive

Now that you are a pro at calling anonymously, let’s talk about the opposite situation. What to do when YOU receive a call from a blocked number? It can be intriguing at times, often very annoying.

Can you call back a blocked number?

In general, the answer is no. If someone has gone to the trouble of hiding their number, it is very difficult, if not impossible for an individual, to call it back directly.

However, some carriers offer a service that allows, within minutes of the call, to call back a blocked number. But this is not a universal solution and its effectiveness may vary.

How to unmask blocked numbers? (Almost) impossible mission!

Let’s be clear: it is nearly impossible to unmask blocked numbers reliably. Services that promise to do so are often ineffective. Only the relevant authorities can, under specific legal circumstances, potentially trace the origin of a blocked call.

So, what to do?

The best strategy is prevention. Most smartphones allow you to automatically block calls from unknown or blocked numbers.

The benefits:

On iPhone:
Go to Settings > Phone > and enable Silence Unknown Callers.
On Android:
Open the Phone app > Settings > Blocked numbers and enable the option to block unknown callers.

These calls will be sent directly to your voicemail without even ringing your phone. Royal peace! 🧘‍♀️️

A man wearing a white mask and a hoodie is looking at his mobile phone on a city street. The image is created in a cartoon or comic style.

💪 Why hiding your number is very important for your privacy

Beyond the technical aspects of how to hide your number, it's essential to understand the concrete benefits for your peace of mind.

The advantages of phone anonymity:

Protect your personal data:
Your number is the key to many of your online accounts. Protecting it means safeguarding your digital identity.
Avoid telemarketing and spam:
This is the number one reason for many of us. By not giving out your number indiscriminately, you drastically reduce the number of unsolicited calls.
Secure your online transactions:
When selling an item on a classifieds site, using a private or temporary number prevents you from being contacted months later.
Maintain professional distance:
Ideal for professionals contacting clients from their personal mobile.
Keep control:
In the end, it's you who decides who can reach you and when. That's true luxury!

Protecting your privacy is not a luxury; it’s a fundamental right in the digital age. By learning how to hide your phone number, you take a significant step towards regaining control of your data.

🕵️‍♀️ Conclusion: It's your turn, secret agent!

And there you go! You now have all the cards in hand to master the art of masked calling. We’ve seen together:

The ultra-simple technique of #31# for occasional needs
How to set up your iPhone or Android to call anonymously all the time
The apps and services that offer even more flexibility and security
How to react to masked calls you receive and the impossibility of unmasking hidden numbers
All the benefits you gain from hiding your phone number to protect your privacy

Hiding your phone number is no longer a secret for you. It's a powerful and easy-to-use tool to navigate more serenely in our connected world.

So, the next time you hesitate to make a call, remember these tips. Take back control of your privacy, one call at a time! Don't hesitate to share this guide with your friends, they too have the right to be secret agents! 😉

🤔 FAQ: Questions everyone is asking

Q1: Does hiding my number also work for SMS?

No, unfortunately. Tricks like #31# or phone settings only work for voice calls. Your SMS will always display your number. For anonymous SMS, you need to use dedicated apps, and luckily, that’s exactly what our service Anonymous SMS offers.

Q2: If I call anonymously, can the person still leave me a voicemail?

Absolutely! If you reach their voicemail, you can definitely leave a message. The only difference is that the person won't see your number displayed.

Q3: How can I tell if #31# worked?

The best way is to test it on a friend's phone (with their permission, of course!). You will immediately see if the call displays as "Private Number."

Q4: Is there a difference between "masked number" and "private number"?

For the user receiving the call, there is no practical difference. Both terms mean that the caller's identity is not displayed.

Q5: Is it possible to unblock the "Show My Number" function if it is greyed out on my iPhone?

Sometimes, certain operators may block this option. If that's the case for you, a quick call to your customer service could resolve the situation.