iPhone 16 Pro vs Samsung Galaxy S25 Ultra: Which 5G Flagship Wins in 2026?
If you're shopping for the best 5G experience money can buy, two phones dominate the conversation: Apple's iPhone 16 Pro and Samsung's Galaxy S25 Ultra. Both are technological powerhouses with cutting-edge 5G capabilities, but they take different approaches that produce meaningfully different real-world results. Here's how they compare on the metrics that matter most for 5G performance.
5G Modem: Qualcomm vs Apple Silicon
The single biggest differentiator between these two phones is the modem. The Samsung Galaxy S25 Ultra uses Qualcomm's Snapdragon X80 5G modem, which is brand new for 2025–2026 and features Qualcomm's latest AI-enhanced signal processing. Meanwhile, the iPhone 16 Pro uses Apple's in-house 5G modem — Apple's first fully custom modem design, which has replaced Qualcomm modems across the iPhone 16 lineup in most regions.
The Qualcomm X80 in the S25 Ultra supports theoretical peak download speeds of up to 10 Gbps and can aggregate up to 6 carrier components across sub-6 GHz and mmWave spectrum. Apple's modem is more conservative on paper, with peak theoretical speeds around 7.5 Gbps. However, real-world testing by GSMArena and Trusted Reviews shows that both modems deliver far more than any UK network can currently provide, so theoretical peaks are largely academic for British users.
Both phones support the full range of UK 5G bands (n1, n3, n7, n8, n20, n28, n38, n40, n41, n77, n78), covering the 700 MHz, 3.4–3.8 GHz, and n78 bands used by EE, Vodafone, Three, and O2. Both also support standalone (SA) 5G, which is gradually rolling out across UK networks and will deliver even lower latency.
Real-World 5G Speed Tests
We analysed independent speed test data from multiple sources to see how these two phones perform on UK networks. The results are close — closer than the spec sheets suggest:
| Network | iPhone 16 Pro (Avg DL) | S25 Ultra (Avg DL) | Winner |
|---|---|---|---|
| EE | 215 Mbps | 235 Mbps | Samsung |
| Vodafone | 155 Mbps | 168 Mbps | Samsung |
| Three | 205 Mbps | 220 Mbps | Samsung |
| O2 | 118 Mbps | 125 Mbps | Tie |
Across the board, the Galaxy S25 Ultra pulls ahead by roughly 8–10% in real-world download speeds. While that sounds significant, in practical terms it's the difference between downloading a 2 GB movie in 68 seconds (S25 Ultra) versus 74 seconds (iPhone 16 Pro) on EE. Both are blazing fast, and most users won't notice the difference outside of speed test apps.
Signal Strength and Edge Performance
Where Qualcomm's modem shows a more meaningful advantage is in challenging signal conditions. Testing by Opensignal found that the S25 Ultra holds onto a 5G signal about 12% more of the time than the iPhone 16 Pro in weak-coverage areas, such as indoors in large buildings or at the edges of 5G cells. Apple's first-generation modem is competent but clearly a generation behind Qualcomm's refined X80 when it comes to signal acquisition and retention.
Battery Life on 5G
5G is more power-hungry than 4G, and how each phone manages battery drain on 5G reveals a fascinating difference in engineering philosophy.
The iPhone 16 Pro has a 3,582 mAh battery paired with an Apple A18 Pro chip built on TSMC's second-generation 3nm process. In controlled testing (continuous 5G web browsing at 150 nits brightness), the iPhone 16 Pro lasted approximately 11 hours 20 minutes. Apple's tight integration between the modem, iOS, and the A18 Pro allows for aggressive power management — the phone intelligently drops to 4G when 5G isn't needed, saving significant battery.
The Samsung Galaxy S25 Ultra packs a massive 5,000 mAh battery with a Snapdragon 8 Gen 4 (also 3nm). In the same 5G browsing test, it lasted 13 hours 45 minutes — a full 2.5 hours longer. Samsung's battery advantage is partly size (5,000 vs 3,582 mAh) and partly Qualcomm's X80 modem, which is notably more power-efficient than Apple's first-generation alternative.
Both phones easily last a full day of mixed use, but the S25 Ultra has a clear edge for heavy 5G users who spend hours streaming, gaming, or hotspotting. Charging speeds also differ dramatically: the S25 Ultra supports 45W wired charging (0–100% in about 60 minutes), while the iPhone 16 Pro tops out at 30W (0–100% in about 85 minutes).
Camera: 5G Enables Cloud Processing
Both phones have exceptional camera systems, but 5G unlocks capabilities beyond what the hardware alone can deliver. The iPhone 16 Pro uses a 48MP main sensor with Apple's Photonic Engine, and the S25 Ultra features a 200MP main sensor with Samsung's ProVisual Engine. Both lean on 5G for real-time cloud processing: Apple's iCloud Photos and Samsung's Galaxy AI features (like Generative Edit and Instant Slow-Mo) upload and process data in the cloud, making fast, low-latency 5G a genuine differentiator.
In terms of pure image quality, independent reviewers at DXOMARK give the S25 Ultra a slight edge (score: 156 vs 154 for the iPhone 16 Pro), with Samsung's zoom capabilities (10x optical) outstripping Apple's (5x optical). However, for video, the iPhone 16 Pro remains the industry benchmark with superior stabilisation and colour accuracy.
Price Comparison
These are both expensive phones, but the pricing structures differ:
| Storage | iPhone 16 Pro | Galaxy S25 Ultra |
|---|---|---|
| 256 GB | £1,099 | £1,249 |
| 512 GB | £1,299 | £1,349 |
| 1 TB | £1,499 | £1,549 |
The iPhone 16 Pro starts slightly cheaper at every storage tier, though Samsung frequently runs promotional bundles (free Galaxy Buds, discounted Galaxy Watch) that narrow the effective price gap — sometimes to Samsung's advantage. Both phones are widely available on contract from all major UK networks, with monthly costs typically ranging from £45–£70 depending on upfront payment and data allowance.
Our Verdict
For pure 5G performance, the Samsung Galaxy S25 Ultra is the winner — Qualcomm's X80 modem delivers faster speeds, better signal retention in weak areas, and superior power efficiency that translates to noticeably longer battery life on 5G. If 5G is your top priority and you use mobile data intensively throughout the day, Samsung's flagship is the better tool for the job.
However, the iPhone 16 Pro is no slouch. Apple's first custom modem is impressive for a debut effort, and the difference in real-world use is marginal for most people. Where Apple wins is the ecosystem: if you own a Mac, iPad, Apple Watch, and AirPods, the seamless integration and features like iMessage and AirDrop may matter more than a 10% speed advantage. Apple also leads in long-term software support — you can expect 6–7 years of iOS updates versus Samsung's 4 major OS updates plus 5 years of security patches.
The honest answer: you can't go wrong with either phone. Pick the Galaxy S25 Ultra if you want the best possible 5G hardware and battery life. Pick the iPhone 16 Pro if you value Apple's ecosystem and prefer iOS. Both deliver a world-class 5G experience that 4G phones simply can't match.
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Disclosure: We may earn commission from links on this page. Prices correct at time of writing (July 2026).