The most direct way depends on your phone service provider

Blocking a number on a landline works differently than on a cell phone because your landline is connected through a service provider — usually a cable company, telephone company, or VoIP service — rather than a device you carry. Most providers offer call blocking as a built-in feature you can activate through your phone, your online account, or by calling customer service. Some services are free; others cost a few dollars per month.

The exact steps depend on which company provides your service and what type of equipment you have. A traditional landline from AT&T, Verizon, or a regional phone company works differently from a VoIP service like Ooma or Magicjack, which works differently from a cable company's phone service. Before you start, you need to know which one you have.

Key Takeaways

  • Most landline providers offer call blocking through your account online or by dialing a code on your phone, and many include basic blocking for free.
  • Traditional phone companies, cable providers, and VoIP services each have different blocking methods, so you need to know which one provides your service.
  • Blocking a single number usually takes seconds once you know your provider's method, but some services require you to call customer service to add numbers to a block list.
  • If your provider does not offer call blocking, a third-party device that sits between your phone line and your phone can block calls for you.

How to block a number through your phone company's website

Most major landline providers let you manage blocked numbers through your online account. Log in to your account with your phone company — AT&T, Verizon, Comcast, Charter, or whoever bills you for phone service — and look for a section called "Call Blocking," "Call Management," or "Phone Settings." You will usually find a field where you can type in the number you want to block, then click a button to add it to your block list.

Once a number is blocked, calls from that number will not ring through to your phone. Some services send blocked calls to voicemail; others hang up silently. The blocked number may or may not hear a message saying the number is not accepting calls. Check your provider's website or call their customer service line to see what happens when someone you have blocked tries to reach you.

If you cannot find call blocking in your online account, your provider may not offer it through their website. In that case, move to the next method or call customer service to ask whether they have a phone-based blocking option.

How to block a number by dialing a code on your landline

Some phone companies let you block a number without logging into an account. After you receive a call from a number you want to block, pick up your handset and dial a short code — usually *60 or *61, depending on your provider — while the call is still active or immediately after it ends. Follow the voice prompts to confirm the number you want to block.

This method works on traditional landlines from AT&T, Verizon, and some regional phone companies. It does not work on all services, and the code varies by provider. If you are not sure which code to use, call your phone company's customer service line and ask them for the call-blocking code specific to your account.

The advantage of this method is that you do not need to remember the number or log into a website — you can block it right after the call ends. The disadvantage is that you can usually only block one number at a time this way, so if you receive calls from many numbers, the online method or calling customer service may be faster.

How to block calls if you use a VoIP service

VoIP services like Ooma, Magicjack, Vonage, and Google Voice each have their own call-blocking system. Most let you log into your account online and add numbers to a block list, similar to a traditional phone company. Some also let you block a number by pressing a button on your VoIP device or by dialing a code.

Check your service's website or the app on your phone to find the call-blocking section. If you cannot find it, log into your account and look for "Settings," "Phone Settings," or "Call Management." If your service does not offer call blocking built in, you may be able to use a third-party app or device instead.

How to block calls if your provider does not offer call blocking

If your phone company does not have a call-blocking feature, or if you want more control over which calls get through, you can buy a standalone call-blocking device. These devices sit between your phone line and your phone and filter incoming calls before they reach you. Popular options include the CPF30 from Clarity and the Call Blocker from Ooma, which cost between $30 and $100.

These devices work by checking incoming calls against a database of known spam and robocall numbers. You can usually add your own numbers to a personal block list through a button on the device or through an app on your phone. Some devices let you whitelist certain numbers so they always ring through, even if they would normally be blocked.

The advantage of a standalone device is that it works with any phone service and does not depend on your provider to add features. The disadvantage is that you have to buy it upfront and maintain it yourself. If your provider already offers call blocking, using their service is usually simpler and costs less.

What to do if you keep receiving calls from the same number

If blocking the number does not stop the calls, the caller may be spoofing their number — using technology to make their call appear to come from a different number each time. In this case, blocking individual numbers will not help because each call appears to come from a new number.

If you are receiving repeated unwanted calls, report them to the Federal Trade Commission at reportfraud.ftc.gov or call 1-877-438-4338. You can also file a complaint with your state's attorney general. These reports help law enforcement track down scammers and robocallers. In the meantime, you can ask your phone company whether they offer a "do not call" filter or spam-blocking service that catches calls from known scam numbers.

Frequently Asked Questions

Can I block a number if I do not know who it is?

Yes. You do not need to know the caller's name or reason for calling to block their number. If you receive a call from a number you do not recognize and do not want to hear from again, you can block it using any of the methods above. Most phone companies will block the number based on the phone number alone.

Will the person I block know that I blocked them?

No. When you block a number, the caller will not receive a notification saying they have been blocked. They may hear a message saying the call cannot be completed, or the call may hang up silently. They will not know it was you who blocked them.

Can I unblock a number after I block it?

Yes. Most phone companies let you remove a number from your block list through the same method you used to add it. If you blocked it through your online account, log back in and delete it from your block list. If you blocked it by dialing a code, call customer service and ask them to remove it.

Does call blocking work on calls from businesses I want to reach?

Call blocking only blocks the specific number you add to your list. If a business calls from a different number, that call will still ring through. If you accidentally block a business number, you can unblock it and the next call from that number will reach you normally.

What if my phone company charges for call blocking?

Some phone companies include basic call blocking for free, while others charge $3 to $5 per month for a premium call-blocking service that blocks more numbers automatically. Ask your provider whether they offer a free option before you pay for a subscription. If the cost is too high, a standalone call-blocking device may be cheaper over time.