Will iPhone 17 Pro and Pro Max Cases Fit the iPhone 18 Pro and Pro Max?

Updated September 23, 2026, with the official iPhone 18 Pro and iPhone 18 Pro Max dimensions.

Short answer: yes. The official dimensions match exactly, and a COCOMII case is cut for both phones in each pair. The published specifications give the iPhone 18 Pro and 18 Pro Max the same height, width and depth as the 17 Pro and 17 Pro Max, which is what case makers had already printed on their packaging in August. COCOMII cuts one rectangular case for each pair, and every design made for the new phones is listed for both models in a single variant. For a case from another brand the body size is settled; the camera opening and buttons are still worth the one-minute check below.

The rest of this guide gives you the published measurements for both generations, explains the five things that actually decide whether any case carries over, and shows you how to test a case you already own in under a minute.

What is confirmed now that the iPhone 18 Pro specs are published?

Everything that decides body fit is now on the record. If the shape itself is new to you, the rectangle phone case guide explains the flat edges, the corners and the magnet ring.

Claim	Status	Source
iPhone 17 Pro and 17 Pro Max dimensions	Confirmed	The official iPhone 17 Pro tech specs page, published September 2025
iPhone 18 Pro and 18 Pro Max keep the 17 Pro and 17 Pro Max height, width and depth	Confirmed	The official iPhone 18 Pro tech specs page, published September 2026
iPhone 18 Pro and 18 Pro Max weight	Changed	211 g and 249 g, up from 206 g and 233 g, on the same official specs page
One COCOMII case fits both the 18 Pro Max and 17 Pro Max, and one fits both the 18 Pro and 17 Pro	Confirmed	How the cases are cut, listed and sold

So the answer is settled for the body and still worth checking for the details. Height, width and depth match to the tenth of a millimeter, for every brand. What no spec sheet lists is the camera plateau, so a case from another brand still has to prove its camera opening and buttons. A COCOMII case is cut and listed for both phones in each pair.

What are the iPhone 18 Pro and iPhone 17 Pro dimensions?

These are the published figures for both generations. Height, width and depth are identical; only the weight moved.

Model	Height	Width	Depth	Weight
iPhone 17 Pro	150.0 mm	71.9 mm	8.75 mm	206 g
iPhone 17 Pro Max	163.4 mm	78.0 mm	8.75 mm	233 g
iPhone 18 Pro	150.0 mm	71.9 mm	8.75 mm	211 g
iPhone 18 Pro Max	163.4 mm	78.0 mm	8.75 mm	249 g

Dimensions as published on the official iPhone 17 Pro tech specs page and the official iPhone 18 Pro tech specs page. Compatibility reporting before the launch: Macworld, August 2026, with the same case-maker packaging covered by Forbes and other outlets. Event date: MacRumors, August 26, 2026.

One gap worth naming: no official specs page has ever listed a camera plateau measurement for any iPhone. Every camera bump figure quoted around the web comes from someone measuring hardware, not from a spec sheet. That is why the camera opening is the part a case maker has to get right by building against the phone, rather than by reading a number off a page, and it is the part most likely to be wrong on a case that only claims to fit.

Why did case makers know the iPhone 18 Pro would fit older cases?

Because case makers know before the rest of us. To have cases on shelves the week a phone ships, the big accessory brands work from the final body specification months ahead, under agreements that keep them quiet. When one of them printed "fits iPhone 18 Pro and iPhone 17 Pro" on the same box in August, that was not a guess. It was a company betting its return rate on the two bodies being the same, and the published numbers proved it right.

The pattern also has precedent. The phone has kept a body size across two generations before, and each time the case market simply carried over. What changes between years tends to be inside the phone, in the camera hardware, or in the finish, none of which alters where the walls, buttons and cutouts sit.

The published numbers settle the body. They do not settle the camera plateau, which no spec sheet lists, and that is exactly why the checklist below still matters for any case that was not cut against the new phone.

What actually decides whether a case fits?

Five things, in the order they tend to fail:

1. Height and width. The body has to sit inside the case walls without forcing.
2. Depth. The iPhone 18 Pro models are 8.75 mm deep, the same as the 17 Pro models, so the side walls are cut to that thickness.
3. Camera opening. This is the one that usually decides it. The opening has to clear the camera plateau on every side.
4. Button placement. Side button, volume, Action Button and Camera Control all have to line up.
5. Magnet alignment. The magnet ring has to sit concentric with the phone's own magnets or chargers slide and the hold weakens.

How do you check any case in under a minute?

If you are reusing a case from another brand, or you just want to be sure, do this before you trust it:

• Seat the phone fully and press each corner in turn. If one corner lifts while another sits flush, the case is the wrong length.
• Look at the camera opening straight on in good light. You want a visible gap of case wall on all four sides, not a lens touching an edge.
• Press each button through the case. Every press should be crisp, with no sponginess and no button held down.
• Put a MagSafe charger on the back and rotate it. It should settle into one obvious center and stay there.
• Hold the phone by the case and give it a gentle shake. Any rattle means movement, and movement means the case is not doing its job.

Pro or Pro Max, and how to tell which you have

The two sizes are not interchangeable, this year or any year. The Pro Max body is 13.4 mm taller and 6.1 mm wider than the Pro, which is far too much for one case to cover both. If you are unsure which model you are holding, open Settings, then General, then About, and read the Model Name line. It is worth thirty seconds, because a Pro Max case leaves the smaller phone loose and the camera opening misaligned.

Why keeping a case across generations has become the point

There is a quiet shift in how people think about this. A phone is replaced on a cycle. A case, if it is the right one, is the part you actually see and touch all day, and increasingly it is the part people are unwilling to give up. The question "will my old case fit" used to mean saving money. Now it more often means keeping a look you chose on purpose.

The rectangular silhouette makes that choice easier to justify. Flat side walls meet the phone along its whole height instead of pinching at a curve, so the fit is even and the case does not creep loose in a pocket. The sharp right-angle corners give a thumb something to brace against, which is the reason a boxy case feels more secure in the hand than its slimness suggests, and the flat profile slides into a pocket more predictably than a rounded one. A shape that behaves this well on the 17 Pro behaves the same way on a body the published specs show is identical.

That is the thinking behind cutting one case for each pair of models rather than a separate case per year. The iPhone 18 Pro Max and 17 Pro Max collection and the iPhone 18 Pro and 17 Pro collection are listed that way for every design made for the new phones, from Abalone Shell to embossed Crocodile, with the magnet ring built in rather than added on. If you like the ring on its own, the MagSafe ring is sold separately too.

Frequently Asked Questions

Ready to choose a finish? Start with the rectangular iPhone 18 Pro Max and 17 Pro Max cases or the iPhone 18 Pro and 17 Pro cases.