Apple is not officially endorsing the use of iPhone 17 Pro cases with its iPhone 18 Pro models, although testing by technology writer John Gruber suggests existing cases may still fit.
Writing in Daring Fireball, Gruber said he asked Apple about compatibility between the two generations. The company pointed to a slightly thicker camera plateau on the iPhone 18 Pro as the reason it does not consider the cases interchangeable.
Using a digital caliper, Gruber measured a difference of 0.1mm, recording 11.5mm on the newer model compared with 11.4mm on its predecessor. He also reported that Apple had increased the camera plateau’s protective lip on its new cases by the same amount.
Despite that change, Gruber said iPhone 17 Pro cases fitted the corresponding iPhone 18 Pro models in his testing. Cases supplied by Apple for the newer phones also fitted the previous generation. He noted that the phones retain the same height, width and body thickness.
The findings suggest some owners may be able to reuse their existing cases. However, a successful fit in one reviewer’s testing does not establish compatibility or equivalent protection across every case design.
For buyers, the distinction is between a case that physically fits and one officially supported for the device. The reported results offer scope for reuse, but do not support a blanket assurance that all older cases will work.
