How to transfer contacts from iphone 4 to iphone 6?

I just got a new phone and a new sim card with a different number and need to transfer all of my contacts, I have heaps and heaps so I really don't want to do this manually.

I dson't think you can, since its a different number. You could ask the phone company or maybe you could do it with the icloud thingy (I'm not too sure, because I have an Android).