Yes an iPhone 6s will fit the iPhone 6 lifeproof case but not perfectly... The camera is not perfectly centered, but this is my first time having a lifeproof case so I do not know if that's ever been a problem. It doesn't bother me and it does not affect the photos. If you look where the headphones go and where you plug in your phone to charge it, it's not completely closed, but it's not really noticable. There's a covering over where you charge your phone if it were to be opened the gap increases in size and you can see a difference when it's opened or closed it's not at all bad. I got a little rainbow in the bottom left courner, but it's so tiny I don't even notice. It's kinda hard to get the back piece on, but I got it on. Starting from the bottom and alternating sides as you go up was the easiest way I found. When you push down the back piece when the case is fully closed there is a little room. I'm trying to say yes it fits. It was easy to fit the phone into the front piece. Would it withstand the elements with the tiny gap? Well, I'm not sure because I haven't tested, but by the looks of it I would say yes. Over all it fits good, still looks good, I love it, and would recommend a friend an iPhone 6 Lifeproof case for an iPhone 6s.