Your landline has built-in blocking tools, but which one works depends on your phone company and phone model

Most landline blocking happens at two points: your phone company's network (before the call reaches your house) or your actual phone or device (after it arrives). Network-level blocking is usually faster and stops the call before it rings, but it costs extra or requires you to use a specific service. Device-level blocking — using your phone's built-in features or an answering machine — is free but means the call still comes through to your line before it gets blocked.

Your phone company almost certainly offers at least one blocking service. Call your provider's customer service line (the number is on your bill) and ask what call-blocking options they have. Some are free; some cost $3 to $5 per month. If you want to block calls yourself without paying extra, your phone or answering machine may have a manual block feature that lets you enter numbers one at a time.

Key Takeaways

  • Your phone company can block calls at the network level before they ring your phone, but this usually costs $3 to $5 per month or is included only in premium service packages.
  • Most landline phones and answering machines have a manual block feature that lets you enter specific numbers to reject, and this costs nothing.
  • Robocall-blocking services like Nomorobo work with landlines if your phone company supports them, and some are free while others charge a small monthly fee.
  • Caller ID is often a separate service from your phone company; if you do not have it, you cannot see the number to block it manually.
  • If you share a line or have a business number, blocking may affect other people on that line, so check with them first.

Network-level blocking through your phone company

This is the most effective method because it stops calls before they reach your house. Your phone company operates the network that carries the call, so they can reject it at that stage. The downside is that most phone companies charge for this service — typically $3 to $5 per month — though some bundle it free with higher-tier service plans.

Call your phone company's customer service number (printed on your bill) and ask about their call-blocking or call-screening service. Common names include Call Block, Call Filter, Nomorobo (which some companies offer as an add-on), or similar branded names. Ask whether it blocks specific numbers you provide, blocks entire categories (like suspected robocalls), or both. Some services let you create a whitelist — a list of numbers that always get through — which is useful if you want to block everything except family and close friends.

Once you sign up, the service usually takes effect within 24 hours. You will typically manage it through a web portal or by calling a phone number to add or remove blocked numbers. Keep your phone company's support number handy in case you need to troubleshoot or adjust your settings.

Manual blocking on your phone or answering machine

If you do not want to pay for a service, most landline phones and answering machines have a built-in block feature. This requires you to enter the phone number manually, and it only works if you have Caller ID so you can see which number to block. The blocked number will still ring your phone once, but your phone will reject the call before it connects.

To use this feature, look for a button or menu option on your phone labeled "Block," "Reject," or "Do Not Disturb." The exact steps vary by phone model, so check your phone's manual or search online for "[your phone model] how to block a number." Typically you will scroll to a recent call, press a block button, and confirm. Some phones let you block up to 30 numbers; others hold more. Once a number is blocked, calls from that number will not ring through.

If you have an answering machine, it may have its own block list separate from your phone. Check the answering machine's manual for instructions. Some machines let you block numbers by pressing a button after you hear the call; others require you to enter numbers through a menu.

Robocall-blocking services that work with landlines

Nomorobo is the most widely known robocall blocker for landlines. It works by analyzing incoming calls in real time and rejecting ones that match known robocall patterns. Some phone companies offer Nomorobo free as part of their service; others charge $1 to $2 per month. A few phone companies do not support it at all, so ask your provider first.

To use Nomorobo, you typically call a phone number to set up it, or you sign up through your phone company's website. Once active, suspected robocalls are blocked before they ring your phone. You can also report calls as robocalls through a web portal, which helps Nomorobo improve its detection. The service does not require you to enter numbers manually — it works automatically based on call patterns.

Other robocall-blocking services exist, but availability on landlines is limited. Most are designed for cell phones. Ask your phone company which services they support on your landline plan.

Do Not Call Registry and complaint reporting

The National Do Not Call Registry is a free list maintained by the Federal Trade Commission. If you register your landline number, telemarketers are legally required to stop calling you within 31 days. Robocalls and scams are not required to follow this rule, but registering still stops legitimate telemarketing calls.

To register, visit donotcall.gov or call 1-888-382-1222 from the phone you want to register. Registration is permanent — your number stays on the list even if you move or change providers. You can register multiple numbers if you have more than one landline.

If you receive calls from the same number repeatedly after registering, or if you believe you are being targeted by a scam, you can file a complaint with the FTC at donotcall.gov. The FTC does not stop individual calls, but complaints help them identify patterns and take action against large-scale violators. You can also report robocalls to your phone company; many use this data to improve their blocking services.

Caller ID as a foundation for manual blocking

Caller ID is a separate service from call blocking, but you need it to block calls manually. Caller ID shows you the phone number (and sometimes the name) of the person calling before you answer. If you do not have Caller ID, you cannot see the number to block it, and manual blocking is not possible.

If you do not have Caller ID, call your phone company and ask to add it. It usually costs $8 to $12 per month, though some providers include it free with certain plans. Once you have Caller ID, you can see incoming numbers and decide which ones to block. Some phones display the number on a small screen; others announce it through a speaker or read it aloud if your phone has that feature.

If you receive calls from numbers that appear to be spoofed (fake numbers designed to look local or official), Caller ID will show the spoofed number, not the real source. Blocking the spoofed number stops that one call but not future calls from the same scammer using a different fake number. This is why network-level robocall blocking or Nomorobo is more effective against scams than manual blocking alone.

Shared lines and business numbers: what to consider

If your landline is shared with other household members or used for a business, blocking a number affects everyone on that line. Before you block a number, make sure no one else needs to receive calls from it. A blocked number will not ring through for anyone, so if you block a number by mistake, you will need to unblock it through your phone or call your phone company to remove it from their network-level filter.

For business lines, consider whether blocking might cause you to miss important calls. Some businesses use shared numbers or call from different numbers, so blocking too aggressively can hurt your business. If you run a business and receive many unwanted calls, a network-level service with a whitelist (allowing only known numbers through) may work better than blocking individual numbers.

Frequently Asked Questions

Will blocking a number stop all calls from that person?

If you block at the network level through your phone company, yes — the call is rejected before it reaches your house. If you block on your phone itself, the call will ring once before being rejected. Scammers often use different numbers each time, so blocking one number does not stop future calls from the same scammer using a new number.

Can I block calls from a specific area code or country?

Some phone company services let you block entire area codes or international calls, but this is not a standard feature on most landline phones. Ask your phone company whether their call-blocking service offers this option. If it does not, you may need to use a third-party service or block numbers individually as they call.

What happens if I block a number by mistake?

You can unblock it by going back into your phone's block list or calling your phone company to remove it from their network filter. The process takes a few minutes. If you unblock a number quickly, you should not miss any calls from that person.

Do I need to pay for call blocking, or is there a free option?

Manual blocking on your phone is free if your phone has the feature. The National Do Not Call Registry is free. Network-level blocking through your phone company usually costs $3 to $5 per month, though some providers include it free with premium plans. Nomorobo costs $1 to $2 per month through most providers, or is free if your company offers it.

Can I block calls from unknown numbers or private callers?

Some phone company services can block calls that do not display a number (private or blocked callers), but this also blocks legitimate calls from people who have their number hidden. Most people prefer to let these calls ring so they can decide whether to answer. If you want to block all private callers, ask your phone company whether their service supports this option.