How to Block Calls That Do Not Show Up on Caller ID

Caller ID is a useful tool to screen unwanted calls. However, some calls do not show up on caller ID, or are listed as unknown name or unavailable. When this occurs, you are left with the choice of picking up or seeing if the caller leaves a message. A variety of steps allow you to block these numbers and avoid the hassle of unwanted phone calls, effectively manage unknown callers and ameliorate the hassles posed by telemarketers.

Instructions

1. Register your phone number with the federal Do Not Call Registry to eliminate many unwanted calls, particularly those showing up as unavailable or unknown name. Telemarketers are required by law to not call numbers on the list unless a prior business relationship has been established. Visit donotcall.gov to register your phone number, or call [phone]. For TTY service, dial [phone].

2. Press *77 to activate anonymous call rejection on your phone. Calls marked private will no longer be able to ring your number. Note that calls marked unknown and unavailable will still get through. Anonymous call rejection is designed to prevent those who are hiding their numbers from reaching you. Press *87 to deactivate the service.

3. Press *61 to flag a number with a priority ring. Priority ringing makes your phone ring differently when certain numbers call you. If you don't know the number that just called, hang up then press *61 to add the number to your priority ring list. Placing unknown numbers on your priority ringing list is a way to give an immediate heads up when that number calls again.

4. Press *60 on your phone immediately after hanging up from an unwanted phone call. This will place the number in your own personal blocked caller list, even if you could not see the number on caller ID. The feature usually costs a few dollars a month. Check with your local service provider for details on adding the call block feature. Press *80 to deactivate the service.

5. Activate Privacy Manager if you use AT&T, or a similar service if you use another carrier. Calls marked unknown, unavailable or otherwise obfuscated are challenged before your phone rings. An access code can be provided to friends and relatives so they can reach your line directly if calling from a number marked private. All others must state their name. Your phone rings, caller ID shows "Privacy Manager" and you can reject the call, send it voicemail or pick up.

Tips & Warnings

• Different carriers may use different functions to achieve similar results. Always check with your local provider for directions specific to your phone line.

References

• AT&T User Guides, Call Blocking
• AT&T Anonymous Call Rejection
• AT&T User Guides, Privacy Manager

Resources

• National Do Not Call Registry
• Stopping Harassing Phone Calls