Does your old case fit the iPhone 18 Pro?

In terms of size it fits: the iPhone 18 Pro is the same as the iPhone 17 Pro down to a tenth of a millimetre — 150.0 by 71.9 by 8.75 mm. The number of cameras has not changed either: like the 17 Pro, the 18 Pro has three rear cameras. A 17 Pro case therefore usually fits the 18 Pro too; the only thing to check is the camera cut-out, because that is where a case sits tightest.

Below are Apple's official measurements side by side, what has actually changed, and how to work out in thirty seconds whether your old case can stay.

The measurements side by side

These are Apple's own figures, not a retailer's or a rumour's.

Height, width and depth are identical. Only the weight goes up: 5 grams on the Pro, 16 on the Pro Max. You feel that in your hand, but a case does not notice it at all.

So what has changed?

Very little has changed as far as a case is concerned. This is what is different:

• The same three lenses. Apple lists three rear cameras on the iPhone 18 Pro: the 48 MP main camera, a 48 MP ultra wide and a 48 MP telephoto (4x, and 8x at 12 MP). That is the same number as on the 17 Pro.
• A variable aperture. The main camera can now switch between ƒ/1.48 and ƒ/4.0. That is a property of the camera itself; on its own it makes no difference to how your case fits.

When does your old case still fit, and when not?

It depends entirely on how the camera cut-out of your case is shaped.

Good chance it fits if your case has one generous, rectangular opening that leaves the whole camera plateau clear. The phone itself is the same size, so the fit around the edges is right and the buttons line up.

Check it more carefully if your case has separate round rings per lens, or an opening cut tightly around the lenses. If the edge sits even slightly over a lens, your photos do not just get darker — they become unusable.

Watch the edge as well: cases that close exactly around the plateau often will not quite press over the new module, or they go on but sit proud.

Test it in thirty seconds

1. Put your old case on and look straight at the camera from the back. Are all three lenses completely clear? If not, that settles it — the case cannot come along.
2. Take one photo at each zoom setting: ultra wide, 1x, 4x and 8x. A dark edge or a vague shadow in a corner means the lens is looking past the case. That does not improve.
3. Feel the edges. If the case sits proud anywhere, or creaks when you press it, the camera is pushing against it.
4. Test your charger. Does the MagSafe charger click on and charge? With cases that have built-in magnets this usually works; the iPhone 18 Pro supports MagSafe at up to 25 watts.

If your case passes all four steps, keep using it. If it fails at step 1 or 2, there is no point persevering.

Pro or Pro Max: which size do I have?

The two differ by more than 13 mm in height and 6 mm in width, so a case for one never fits the other. If you are not sure, look in Settings > General > About for the exact model name. Or lay the phone on a ruler — 150 mm is the Pro, 163 mm the Pro Max.

Why a case made to measure matters

A case that "also fits the 18 Pro" is usually a case designed for another model that happens to go around it. You notice it in three ways: play around the buttons, a camera edge that does not line up, and a raised edge that is just too low to keep your screen off the table.

Our cases are made per model. The cut-outs for camera, buttons and port line up exactly, there is a raised edge around screen and camera, and the MagSafe magnets are built in. Choose your model in the Alcantara phone cases — there is a version for the iPhone 18 Pro and one for the 18 Pro Max, in seven colours.

Frequently asked questions

Does an iPhone 17 Pro case fit the iPhone 18 Pro?

In terms of dimensions, yes — both measure 150.0 × 71.9 × 8.75 mm. Both phones have three rear cameras, so it usually fits. Do check the camera cut-out: with a single large opening the odds are good; with separate lens rings or a very tight opening it may not line up.

Does an iPhone 17 Pro Max case fit the iPhone 18 Pro Max?

Same story. Both Pro Max models are 163.4 × 78.0 × 8.75 mm, so the fit around the edges is right; just check the camera cut-out.

Does an iPhone 18 Pro case fit the 18 Pro Max?

No. Those two differ by 13.4 mm in height and 6.1 mm in width. It is not a matter of pushing harder — it simply does not go.

Does my old MagSafe case still work on the iPhone 18 Pro?

The iPhone 18 Pro supports MagSafe and charges with it at up to 25 watts. If your old case has magnets built in and otherwise fits well, your charger, stand and card holder normally click straight on. Always test it with your own accessories.

Is the iPhone 18 Pro heavier than the 17 Pro?

Slightly: 211 grams against 206. On the Pro Max the gap is larger, 249 against 233 grams. For your case it makes no difference.

Does my screen protector still fit?

The screen is the same size (6.3 inches on the Pro). To be safe, buy a protector that is explicitly made for the iPhone 18 Pro.

Where do I buy a case that definitely fits the iPhone 18 Pro?

From a case made explicitly for this model, not one that is "also" suitable for it. Our Alcantara cases come per model, with a matching MagSafe card holder in the same colour. Our case for the iPhone 17 Pro also fits the iPhone 18 Pro, and our case for the iPhone 17 Pro Max also fits the iPhone 18 Pro Max. We have tested this ourselves. This only applies to the cases we sell ourselves; we cannot speak for cases from other brands.

In short

The iPhone 18 Pro is the same size as its predecessor, so your old case will probably slide around it. The one thing a case really has to get right is the camera cut-out, and because the 18 Pro has three cameras just like the 17 Pro, the odds are good that it fits. Still, check the cut-out before you assume it is fine.

Want to know more about the material our cases are made of? Read what Alcantara is.