Q: Two iPhones ringing same time

If both devices are sharing the same Apple ID and are on the same Wi-Fi network, this is what will happen. It is part of continuity. Go into Settings>Facetime>iPhone Cellular calls, and turn that off. This will only occur when both devices are logged into the same Apple ID and Wi-Fi network.

I had the same problem. Thank you for the advice....it worked 

You are the only one among 4 Verizon techs and 1 Apple tech who understood the problem which led to the solution.  IOS 8 is new and the feature of having your iPhone ring on your iPad is new but Apple dropped the ball when not telling those on Family Sharing Plans, who also share the same Apple ID, and who are using the same wifi network, that ALL of their devices may ring if just one of their phones is called.  Using your advice I turned off "iPhone Cellular Calls" on every phone but mine and the problem was finally solved. 

Glad to help.

Tremendously helpful - lots of searching in settings, knew it was there somewhere, but would not have thought to check the FaceTime tab. Odd that it is enabled by default. Suspect a lot of people surprised at the first time all their phones ring at once. Thanks!!

I spoke to 2 different Verizon Wireless tech and they told me only way to resolve it is to get a new Apple ID for the other phone(used by my wife).  They told me that is the only way to resolve the problem.  I tried your suggestion and it worked beautifully.  Thank you.

I wonder if these tech people are trained or not :-)

Thank you so much. Three times to the Apple Genius Bar, and no Tech could figure it out.

Hilarious! It just happened to me; five minutes ago....I goggled "my wife's phone rang on mine" and it came right to this post. It was like reading my own description of events... Problem resolved.  Thanks!

Same thing just happened to me.  Google took mer ight here although searching in Apple iPhone community did not...

my wife and I use the same id so do i disable hers or mine?

Family Sharing has nothing to do with it.  It has to do with using the same Apple ID under Messages or FaceTime.  And Apple never told you to use the same Apple ID for Messages or FaceTime on  devices used by different people.

They are.  If you use the same Apple ID on multiple devices for Messages & FaceTime, you will get message/call crossover.

Each individual person should always be using their own unique Apple ID for iCloud, iMessage & FaceTime.

Frequently asked questions about Apple ID

Can I share my Apple ID with someone else?

You shouldn't share your Apple ID account information with other people. Each person should have their own Apple ID.

You don't disable either Apple ID.  You decide who's going to keep using that Apple ID primarily.  Then, the other person signs out of the Apple ID on his or her device(s).  Then, he or she creates a new Apple ID, then he or she signs into that Apple ID on the device.

There are reasons that families with minor children do not want those children to have separate Apple IDs.  For those families, turning off "Use Cellular Calls" in FaceTime eliminates the problem of more than one phone ringing at the same time.  Agreed Verizon Family Sharing has nothing to do with the issue.