It looks like the iPhone 18 Pro and iPhone 18 Pro Max may have different modems inside. On Apple's technical specifications page for the new devices, the iPhone 18 Pro lists Apple's C2 modem, but the iPhone 18 Pro Max lists no modem at all in the U.S.
The same information is also listed on Apple's announcement for the iPhone 18 Pro models.
Both models feature N1, an Apple-designed wireless networking chip that enables Wi-Fi 7, Bluetooth 6, and Thread. iPhone 18 Pro introduces C2, Apple's next-generation cellular modem system, which brings AI-powered improvements to cellular quality and reliability.
The lack of a C2 mention for the Pro Max might seem like a mistake at first glance, but the separate Pro and Pro Max model numbers actually list different LTE bands. On the U.S. Pro specification list, there's a Band 106, but there's no Band 106 on the Pro Max list.
It is not known why Apple would use different modems for the iPhone 18 Pro and iPhone 18 Pro Max, but there were rumors before launch that some devices would continue to use Qualcomm modems.
Apple is also using the C2 modem for the iPhone Duo, so it's possible there were supply issues. It appears both the new iPhone 18 Pro and iPhone 18 Pro Max may use the C2 modem outside of the U.S., so the split could be U.S. only.
The C2 modem supports both sub-6GHz and mmWave 5G, and Apple says it includes AI improvements to cellular quality and reliability. It is faster and more energy efficient than the C1X modem, but it's not yet clear how it compares to the Qualcomm modem in the 18 Pro Max.
Apple's new iPhone 18 Pro models will go on sale on September 18, with preorders to take place on September 12. Pricing on the iPhone 18 Pro starts at $1,199, while pricing on the 18 Pro Max starts at $1,299.
