How can I block a number using my iphone ?

You can always block that number on Verizon’s website if you have an online account. When I had Verizon, I was able to block any number from calling me on their website. Blocking numbers should be free. You could always call Verizon and ask about blocking numbers on an iPhone.

I have heard of an iPhone app called iBlacklist that will allow you to block phone numbers, but you’d have to jailbreak your phone, as the iPhone does not have a feature on the device itself to block unwanted numbers. According to Apple, jailbreaking an iPhone will void your warranty, so you may not want to go that route.

I find that blocking numbers is often more of a hassle to do than it’s worth because the iPhone doesn’t have that option built-in. And, according to a few Verizon techs, the iPhone is not compatible with certain other features of the Verizon network, like the Call&Message Block that @AshlynM mentions either. Yet another reason I went Android; I like features. That Apple logo severely limits your features and options.

There is a $1.99 app called Blacklist which is like the iBlacklist that @AshlynM recommends except that you don’t need to jailbreak your phone. The catch is that it’s crap; like many other apps, it is pure snake oil. If you want an app that actually does block numbers, you will need to jailbreak your phone with all of the risks and consequences that entails.

But there is also the “Silent ringtone”, which seems to be the most common method as it is easy, free, and doesn’t void your warranty. This is likely your best option.

Personally, most of the people I want blocked are not the type to leave messages, so I set my Droid X to kick those numbers directly to voicemail, secure in the knowledge that they won’t fill my inbox.

@jerv – What is the silent ringtone and how do I do it ?

There are some available for download, but it’s basically a normal custom ringtone except that instead of a song or sound, it’s silence. That way, it still technically plays a ringtone and all, but you don’t hear it because there is nothing to hear.

Then you go into your address book and set that ringtone to that particular contact.

The catch is that you will always hear the first one from a particular number, but if you add them to the contact with a silent ringtone, you won’t hear them after that.