Apple C1 vs Qualcomm Modem Performance [Speedtest]

Apple finally launched its long-awaited in-house 5G modem, the C1, in the new iPhone 16e. This marks a shift away from Qualcomm, its long-standing modem supplier. With early adoption underway, Ookla's Speedtest Intelligence offers an early look at how this new modem stacks up against the iPhone 16, a device with similar specs but a Qualcomm Snapdragon X71 5G modem.

The analysis, based on data from March 1 to March 12, 2025, highlights key performance differences across AT&T, Verizon, and T-Mobile networks. Both the iPhone 16e and iPhone 16 share the A18 SoC and a 6.1-inch display, but the 16e lacks mmWave 5G support, a first for a U.S.-market iPhone. Ookla's findings show the C1 modem delivers mixed results depending on the carrier, but perhaps better results than initially expected.



For median download speeds, iPhone 16e users on AT&T and Verizon saw gains over the iPhone 16, hitting 226.90 Mbps and 140.77 Mbps, respectively. T-Mobile told a different story. There, the iPhone 16e lagged at 264.71 Mbps compared to 357.47 Mbps on the iPhone 16, a gap of at least 24%. T-Mobile's standalone 5G network, with its deep spectrum and carrier aggregation, likely favors the Qualcomm modem's capabilities over the C1's more limited 5G SA support.

Upload speeds painted a brighter picture for the iPhone 16e. Verizon and AT&T users experienced better performance than their iPhone 16 counterparts, with AT&T showing a significant jump from 8.60 Mbps to 14.63 Mbps. T-Mobile users saw a slight edge on the iPhone 16e, though the difference was less pronounced.



Looking at performance extremes, the iPhone 16e outperformed the iPhone 16 at the bottom 10th percentile across all three carriers. For instance, T-Mobile's slowest iPhone 16e users hit 57.34 Mbps, while iPhone 16 users dropped to 27.27 Mbps. At the top end, however, the iPhone 16 pulled ahead. Its 90th percentile users on T-Mobile reached 889.83 Mbps, far exceeding the 627.01 Mbps of the iPhone 16e.

Verizon's network lagged behind AT&T and T-Mobile in median download speeds for both devices, despite the iPhone 16's mmWave support. The absence of mmWave in the C1 modem didn't drastically hinder the 16e, though it may affect peak performance in specific high-band areas.

Apple's move to the C1 modem follows its 2019 acquisition of Intel's modem business, aiming for greater control over its hardware. The C1 supports low and mid-band 5G, Wi-Fi 6 with 2x2 MIMO, and Bluetooth 5.3, but skips mmWave and Wi-Fi 7, features present in other iPhone 16 models. Apple touts the C1's power efficiency, paired with a redesigned interior that boosts the 16e's battery life to 26 hours of video playback, compared to 22 hours on the iPhone 16.

Early data suggests the C1 modem offers solid performance for worst-case scenarios and upload speeds, particularly on AT&T and Verizon. Yet, its limitations on T-Mobile's advanced 5G network and lack of mmWave support leave the iPhone 16 ahead in peak download performance. As usage increases, ongoing testing will offer a clearer picture of how the C1 modem holds up. Notably, reports suggest that Apple is already working on a refreshed C1 modem with mmWave support.

Check out the full speed test report at the link below and please download the iClarified app or follow iClarified on Twitter, Facebook, YouTube, and RSS for more Apple updates.

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