How to Find a Blocked Telephone Number
It can be frustrating to see a blocked caller ID when your phone rings because you don't know if it's a call you want to answer, such as from a friend, or a call you'd just as soon avoid, such as from a telemarketer. There are techniques and services (some free) that can help you unblock, or unmask, a blocked caller ID and find its phone number.
Let the call go to voice mail. The easiest way to find a blocked phone number is to let the call go to voice mail, then listen to the message. Often, people leave their names, phone numbers and reasons for their calls in messages.
Redial the call. Many landline and cell phones have "Redial" buttons---simply press the Redial button after the incoming blocked call. If a person answers, explain you received a blocked call from that number and politely request that person's name and phone number. It may be you get that person's voice recording, in which he identifies his phone number. If your phone doesn't have a Redial button, check your phone documentation for a redial feature, or contact the phone manufacturer and inquire if your model has a redial feature.
Press *69. In North America, many landline and cell phone carriers offer this code, which (depending on your carrier) might charge a fee per use. You must press *69 immediately after the blocked call, as this code works only with the last incoming call. For some carriers, you will hear a recording with data about the last incoming call (the phone number, time and date of the call) and be prompted if you'd like to return the call (References 1). Some carriers do not provide this recording, but instead place a call back to the last incoming call phone number (in which case you can either ask the person who answers for her phone number, or listen to the voice message which may contain the phone number). Contact your carrier (whose phone number is on your monthly statements) to find out if they offer *69.
Purchase a phone number unmasking service. One such service is TrapCall, which unmasks blocked caller IDs, instead displaying the caller's name and/or phone number. For a free trial, go to Trapcall.com, press the "Try Trapcall free!" button in the lower left of the web page, and follow the instructions.
Purchase an unblocking service. One such service is Unblock Private Numbers that forwards your incoming blocked calls (including those marked "private") to a toll-free number that unmasks the blocking and returns the caller's name and/or phone number to your caller ID. To sign up for this service, go to Unblockprivatenumbers.com, scroll down to "Step By Step Instructions," click the "Click here" link in Step 1, and follow the instructions.