- Codes such as #31# or 067 can be used to hide the caller ID on calls from mobile phones and landlines.
- Setting the hidden number permanently is possible in Android, iOS and some modern fixed ones.
- Using a hidden number is legal but has limits, and outgoing calls are recorded on your bill, with some exceptions.
On many occasions, we find ourselves looking for ways to Calling by phone without our number or the call made appearing detailed on the billWhether for privacy reasons, for specific business purposes, or simply to maintain anonymity, questions arise about how hidden calls actually work and the information telephone companies record.
If ever you wondered How you can make private calls from your mobile or landline and what information is actually recorded on the billThis article compiles all the methods, codes, settings, and related legal details so you can act with knowledge and maximize your phone privacy.
Codes and methods to hide your number when making calls
One of the fastest and most used ways to prevent the person you are calling from seeing your number is use a specific code (prefix) before dialing the destination numberThese prefixes vary depending on the country and the type of line you're calling from. In Spain, there are different combinations depending on whether you're calling from a mobile phone, a landline, or a national or international number.
For mobile to mobile or mobile to landline calls, the standard code is # 31 #You must dial it just before the number you wish to call. For example: # 31 # 600123456This method is immediate and only affects the specific call you make with that prefix, so you'll have to repeat it if you want to hide your number on each subsequent call.
When the call is from a landline to a mobile, the code varies. In this case, you must dial 067 followed by the destination phone number. Example: 067600123456This way, the recipient won't see your number and it will appear as private or blocked.
To Landline-to-landline calls in Spain, the prefix is also used # 31 #. So, if you mark # 31 # followed by the destination landline number, you will keep your identity hidden.
In some countries or systems, you may encounter the prefix * 67. For example, for lines associated with services such as Google Voice in the US, if you dial * 67 followed by the number, the call will be received as hidden. Always check the regional code if you're calling from outside Spain.
If you want to make this setting permanent and have all your calls go through with a hidden number, you can do so from the settings menus on Android and iOS, as well as saving the numbers in your address book with the corresponding prefix.
Permanent hidden number settings on Android and iPhone phones
If you prefer not to rely on remembering the code on each call, you can configure your smartphone so that all calls always go to a private numberBoth Android and iOS offer this feature, although it may vary slightly depending on the version or device customization.
To Android, the usual steps are:
- Access the Phone app or Calls on your mobile.
- Sign in Settings or in the Call Options.
- If you have two SIM cards, choose the line you want to act on.
- Search More adjustments o Advanced settings.
- Select option Issuer ID o Caller ID.
- Choose Hide number and confirm the action.
On some devices, this feature may also be found in the General settings from the phone, in the calls section.
In the case of iPhone / iOS:
- Open the app Settings of the iPhone.
- Scroll down and select the option Phone Number.
- Accede to Show caller ID.
- Deactivate the option, and your calls will go out with a hidden number until further notice.
To reverse this setting and display your number again, simply repeat the steps and re-enable the corresponding option.
Landline Phone Solutions and Additional Tips
Many landlines also allow you to make hidden calls. If you have a modern landline telephone with memory and address book, you can save contacts directly with the preferred one # 31 # so you don't have to dial it every time. However, on older models, you'll have to enter the code manually for each call. This method is also useful for managing the visibility of other features on your phone..
If your device doesn't allow you to set up automatic hiding, remember that the prefix method will always work, both on cordless and traditional corded phones.
Some carriers, such as Orange, offer permanent activation services by calling their customer service. If you're a customer, you can call the customer service number to activate the activation or receive specific help from your provider.
Special codes for specific cases and unhiding the number
In addition to the usual methods, there are quick codes to turn caller ID on and off for each call. For example, if you turned on permanent hidden mode with * 31 #, you can disable it using # 31 # when you want to show your number again.
On some carriers, if you have hidden numbers enabled by default but want your number to be visible to certain contacts, you can select * 31 # before the number. This way, that specific caller will show your ID even if the rest of the call remains hidden.
These speed dialing methods are useful if you have changing needs or are contacting specific people or businesses to whom you do want to share your number.
Hidden calls and their reflection on your phone bill
One of the main doubts is what It actually appears on the bill when you make a call with a hidden number. Companies log every number you call, even if you use private mode.
As a general rule, invoices break down outgoing calls, showing the day, time, destination, and duration, regardless of whether you used the hidden number. If the call doesn't incur a charge because it's included in your flat rate, many companies may not detail the destination, but they do report the total number of calls and minutes used.
In contrast, The calls you receive never appear detailed on your bill.Callers with a hidden number won't leave a visible record on your bill, although the operator may keep an internal record for legal or technical reasons.
In exceptional situations, such as court proceedings, a judge may request a carrier's complete call history, including hidden calls. Outside of these cases, you won't be able to see who called you with a hidden number, either on your bill or through standard apps.
Privacy, legal limits and ethical considerations
The use of hidden number calls is completely legal in Spain, as long as not be used in an abusive manner or to commit illegal actsTelephone anonymity is protected, but abuse (especially mass commercial calls or harassment) can have legal consequences.
La spanish legislation It establishes that only in extreme cases, such as repeated telephone harassment or threats, is it possible to identify the owner of a hidden number, subject to a complaint and judicial authorization. Simply using a hidden number to maintain privacy does not violate any regulations.
However, government agencies and large companies often have switchboards and systems capable of identifying the real number, so anonymity is not guaranteed in all cases. Furthermore, recent laws attempt to limit the use of hidden commercial calls, but the effectiveness of these measures depends on regulation and legal action.
Can I know who is calling me if they use a hidden number?
A recurring question is whether it is possible find out who's calling you when using private modeThe reality is that there is no application or resource available to the user to automatically identify the person who is calling secretly. Many apps They promise this functionality, but they only manage to identify unknown (not hidden) numbers, such as those of companies that are not in your address book. Here you can learn more about how to discover hidden accounts on Android..
The only way to discover the identity behind a hidden number is through legal proceedings, and only in cases of harassment or serious situations, where the telephone company must provide internal records under court order. Therefore, for the average user, the privacy of hidden calls is complete.
Practical uses and additional recommendations
Calling on a hidden number can be useful for contact companies, carry out confidential procedures or protect your personal number. If you only need to hide your number for a specific contact, using the prefix is the best option. If you prefer to maintain anonymity globally, permanent configuration is your ally.
Save sensitive contacts with the code in your address book if you always call them privately. And, although anonymity is guaranteed from private individuals, remember that under the law and by certain agencies, your identity may be revealed if there is a justifiable reason.
Extending anonymity to services and applications
There are services like Google Voice or virtual lines that allow Hide your ID on all calls you make from the platform. Simply access your Google Voice settings, go to "Calls" in the menu, and activate the anonymity option. If you need to choose between multiple numbers, the service allows you to select which one will appear as the sender. These numbers work for both national and international calls, but availability depends on the region and user account. Additionally, for occasional calls from Google Voice, simply enter the country code (in the US, for example, * 67) before the destination phone number when dialing.
Ultimately, Hiding your number is a feature designed to protect your privacy and give you more control over your personal information.Always use these methods responsibly to avoid engaging in harmful or illegal practices.
Today's technology allows you to easily manage how and when to display your personal information when calling, whether from a mobile phone, a landline, or even digital services and apps, with options ranging from the immediate manual method to general device settings. If you have any questions, always consult your carrier's documentation or contact customer service for detailed guidance.
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