Here’s iPhone 17 Pro / Max case compatibility for iPhone 18 Pro / Max users that you need to know about.

Today is the day, and the iPhone 18 Pro and iPhone 18 Pro Max are now officially on sale after months of rumors and waiting. But if you’re upgrading from an iPhone 17 Pro and hoping to keep your case, you’re going to be disappointed. The same goes for using an iPhone 18 Pro case with an iPhone 17 Pro.

That’s the story according to Daring Fireball‘s John Gruber. He reports that Apple told him that the camera area on the iPhone 18 Pro models is slightly thicker than on previous models. The difference is incredibly small at 11.5mm vs. 11.4mm, but it’s enough of a difference to cause an issue.

At least, that’s what Apple says. It makes sense for the company to try to sell new iPhone cases, and the same goes for iPhone accessory makers. However, it’s worth testing your particular case before spending money on a new one — Gruber says that his iPhone 17 Pro cases fit the iPhone 18 Pro without issue.

The same was also the case when using an iPhone 18 Pro case with an iPhone 17 Pro. But we expect that this will very much depend on your chosen case.

The iPhone 18 Pro and iPhone 18 Pro Max are now on sale after going up for preorder last week. Apple’s first foldable, the iPhone Duo, won’t be made available for preorder until the end of October and will go on sale a few days later.