If I Block a Phone Number, does the Person I Call Know I Blocked It?

Mary McMahon
Mary McMahon

When someone chooses to block a phone number, people may know that the phone number is blocked, depending on the type of blocking involved. When people configure a number for blocking, they can usually choose from several options which may either conceal the blocking, or indicate that the number is being blocked. Call blocking can be used on both incoming and outgoing calls, allowing people to remain anonymous when they call out and to avoid calls from specific individuals, or to only accept calls from certain people.

Someone without caller ID cannot see that an incoming phone number has been blocked.
Someone without caller ID cannot see that an incoming phone number has been blocked.

In the case of blocking for outgoing calls, there are two ways to block a phone number. One method involves paying the phone company to block the number, and the other involves selective blocking, in which someone presses *67 before making a call to block the number. If the person being called does not have caller identification, she or he will have no way of knowing that the number is blocked. If the person does have caller identification, the incoming call will show up as “unknown,” “private number,” or “blocked,” allowing the call recipient to see that the number has been blocked or that it cannot be identified.

Call blocking allows people to receive calls only from specific individuals.
Call blocking allows people to receive calls only from specific individuals.

When it comes to blocking inbound calls, a phone subscriber can ask the phone company to selectively block calls from specific numbers, which allows phone subscribers to block a phone number which belongs to a particular person or group, or use a phone screening device which blocks all calls which are made without a special code.

Call blocking allows people who call out to remain anonymous.
Call blocking allows people who call out to remain anonymous.

If calls are blocked by the phone company, when someone dials the number, he or she will hear a busy signal or a message which indicates that the subscriber is not accepting calls from the caller's number. If someone opts to block a phone number in this way, callers will only know that they are being blocked if they hear the recorded message. If a screening device is used at home, a recorded message will play indicating that someone needs to enter a special code to successfully reach the person being called, in which case a caller will obviously realize that his or her number is blocked.

Call blocking may be applied to both incoming and outgoing calls.
Call blocking may be applied to both incoming and outgoing calls.

The drawback to using a blocking device at home is that it blocks calls from everyone who does not have the code. This means that people may miss calls they actually want to receive from people or organizations who do not have the code, including emergency services. For this reason, choosing selective blocking of specific numbers through the phone company is recommended, unless someone has been a victim of telephone harassment, thinks that taking steps to block a phone number belonging to a specific person would not be enough, and would prefer to limit incoming calls to a specific group of individuals such as family and friends.

A telephone owner may have the option to block harassing phone calls.
A telephone owner may have the option to block harassing phone calls.
Mary McMahon
Mary McMahon

Ever since she began contributing to the site several years ago, Mary has embraced the exciting challenge of being a EasyTechJunkie researcher and writer. Mary has a liberal arts degree from Goddard College and spends her free time reading, cooking, and exploring the great outdoors.

You might also Like

Discussion Comments


Word of advice: if ever in an accident, do not give your cell phone number. They put it on the police report and you are harassed to death from that point on. If you do not answer, they keep calling over and over and never leave a message.


I just use *67 before making a phone call if I don't want them to know who is calling. This doesn't happen very often, but sometimes a situation comes up when I don't want them to know who is calling.

This was much more effective before most people started using caller ID. I can understand why people won't answer a call from an unknown number because I would do the same thing. On the other hand, you would be surprised at the number of people who are curious enough to know who is calling and will pick up the phone anyway.


I am supposed to be able to program my landline phone to block certain incoming phone calls, but I haven't been able to get it to work if it comes from a toll free number.

How can I block a phone number like this that is toll free? I have also noticed that some companies will call from more than one number, so you never know for sure if it is them or not.

This is very frustrating to me and I am about ready to get rid of my landline phone altogether but this might only be a temporary solution. If they get a hold of my cell phone can they start calling that number too?


I had a friend who had to take extreme measures to put a block on her phone because of telephone harassment. If this didn't work, she was going to have to completely change her number and make it unlisted.

Only a select group of close friends and family had access to her phone number. This was kind of a pain, but was also scary at the same time. After a period of time she removed the block and thankfully hasn't had any further problems.


I use caller identification to determine if I want to answer a phone call or not. If the company has blocked their number and it shows up as private or unknown, I won't answer it. I figure if the call is important, they will leave a message and I can give them a call right back.

I know that several of my friends do this as well, and imagine that a vast majority of others do this too. It is too bad we have to resort to this, but I get so many telemarketing and political calls and have found this the best way to handle it.


@Pharoah - Yeah, it does seem a little weird you have to call the phone company. It seems like you should be able to do it online, or even block a phone number from a cell phone app! However, you just can't do that with regular phone numbers.

You can do it with one of those Internet based numbers though! I got a Google voice number awhile ago, and I really like it. It's free, and it sends calls and texts right to your cell phone. But the app makes it really easy to block certain phone numbers from calling you, or even send certain numbers straight to voicemail.


Figuring out how to block a phone number from calling you on a cell phone or landline is kind of a pain. Usually you have to call the phone company in order to do it, which seems ridiculous to me! I don't understand why you can't just go to their website and block a phone number. It would be so much faster.


@sunnySkys - That's a good point. However, I think there will always be some people who will pick up a phone call from a blocked number. My grandma does it all the time, even though I've told her over and over again that those calls are usually from telemarketers!


It's good to know how to block a phone number, but I think sometimes blocking your number to make outgoing calls can really backfire. I use my cell phone as my primary phone, and it always shows the number that is calling. It it's a blocked number it shows as "private" or "anonymous."

And I never pick up those calls! So someone with a blocked number is never going to be able to reach me, which kind of defeats the purpose. They've kept their number private, but aren't able to get in touch with me.


If you want the use of your cell phones to last, you had better remember this much: Vote no obama in 2012 and save america! Remember, vote obama out of office in 2012!


What? Are you getting a commission on Kenyan sales? Obviously you should not do any business with any companies in such disreputable countries. Just saying. Most sensible people already know this.


what about changing T-mobile phones to be used outside the U.S., let's say even Kenya because Kenyans have safari, zain yu, orange, etc.

Post your comments
Forgot password?