Apple sells four functionally different versions of the iPhone 18 Pro Max depending on where you buy it, and the gap between the US model and the rest of the world runs deeper than SIM support. A teardown and Apple’s own regulatory filings show the US version gives up Apple’s own modem and a measurable slice of battery life, and Apple has not explained why.
The teardown comes from TechInsights, while spec details come from Apple’s own tech specs pages. Our own coverage of the Qualcomm patent license renewal and Apple’s push toward in-house modems fills in the rest of the picture.
Four Model Numbers, Four Different Phones
Each region gets a distinct model number, and the differences go beyond marketing.
- A3473 (US): eSIM-only, sub-6GHz and mmWave 5G, and the only version with a Qualcomm Snapdragon X80 modem instead of Apple’s own chip
- A3716 (Canada, Japan, Mexico and parts of the Middle East): eSIM-only, Apple’s C2 modem, no mmWave support
- A3717 (UK and most of Europe): a physical nano-SIM tray alongside eSIM, Apple’s C2 modem
- A3718 (China): a physical nano-SIM tray, with the iPhone 18 Pro and Pro Max both activatable there using eSIM or a physical SIM, Apple’s C2 modem
Only the US Model Uses a Qualcomm Modem, and Nobody Knows Why
Every iPhone 18 Pro sold anywhere in the world uses Apple’s own C2 modem, and so does the iPhone Duo. The iPhone 18 Pro Max matches that everywhere except the US, where it still runs Qualcomm’s Snapdragon X80, the same modem found in last year’s iPhone 17 Pro Max.
Apple has not given a public reason for the difference. One theory ties back to Qualcomm’s 2023 announcement that it would supply Apple with modems for smartphone launches through 2026, an agreement separate from the patent license Qualcomm just renewed. If Apple committed to buying a minimum volume of Qualcomm chips through this year, keeping one high-volume model on Qualcomm hardware would be one way to use up that commitment before the deal lapses. Apple has not confirmed this, and it remains a theory rather than a stated reason.
The SIM Tray Costs You Real Battery Life
The clearest, most measurable difference has nothing to do with the modem. Regulatory filings put the eSIM-only Pro Max models at a 5,567mAh battery, compared with 5,391mAh in versions that keep a physical SIM tray. That’s roughly 3 percent more capacity, which Apple translates into about an extra hour of normal use or two extra hours of video playback for the US, Canadian, Japanese and Mexican eSIM-only models over the UK, European and Chinese versions with a SIM tray.
The tray itself takes up internal volume that eSIM-only models can hand back to the battery, so the trade-off is a physical one: keep a SIM slot, and there’s less room for cells.
Apple Markets All Four Versions as the Same Phone
None of this changes what shows up on a spec sheet or a price tag, since Apple sells all four as “iPhone 18 Pro Max” with identical marketing. But it means an iPhone 18 Pro Max bought in London is not the same phone as one bought in New York, down to the chip handling its cellular connection and the exact size of its battery.
Our Take
The battery difference is the one buyers should care about, since an extra hour or two of use is the kind of thing you notice every day. The modem story is more interesting to me as a reporter than as a warning to buyers, since Apple’s own C2 and Qualcomm’s X80 offer comparable real-world performance.
