Apple now says the iPhone 18 Pro has its C2 modem worldwide, but the iPhone 18 Pro Max uses the C2 chip everywhere except in the United States, according to updated technical specifications.
A tipster known as @itspdfu, who has been examining Apple software updates, reported that iOS 27 code indicates U.S. units of the iPhone 18 Pro Max are equipped with a Qualcomm modem instead of Apple’s C2 modem. Apple has not provided an explanation for the discrepancy.
C2 modem rollout and U.S. exception
The report notes that Qualcomm announced in 2023 it would supply Apple with smartphone modems through 2026; the same report suggested this supply agreement could be related to the U.S. exception, but that remains speculative and Apple has not commented. It is unclear which Qualcomm modem is fitted to U.S. iPhone 18 Pro Max units, though the Snapdragon X85 is described as the most likely candidate.
Apple says its C2 modem supports ultra-fast mmWave 5G in the U.S., unlike its previous-generation C1 and C1X modems. Qualcomm modems in iPhone models from the iPhone 12 onward already supported mmWave 5G in the U.S. Apple said the C2 delivers “meaningfully faster uploads” compared to the C1X while consuming 15% less energy.
The modem timeline in Apple devices from the company’s updates: the first-generation C1 modem debuted in the iPhone 16e in February 2025; the second-generation C1X appeared in the iPhone Air in September 2025; and the third-generation C2 is now present in iPhone 18 Pro models except for U.S. iPhone 18 Pro Max units. Apple’s foldable iPhone Duo uses the C2 modem worldwide.
Over the coming weeks, real-world performance tests are expected to show how the C2 and the Snapdragon X85 compare in practice.
