Samsung S25 Ultra vs OnePlus 15: The Phone Battle No One Expected

OnePlus brought its new flagship to the market early, putting the OnePlus 15 up against Samsung’s Galaxy S25 Ultra. Both smartphones are aimed at those buyers who demand a lot from their devices and expect nothing less than long-lasting battery performance, high-quality displays, rapid processors, and regular software updates for years. Pricing, durability, and daily usage have now become the main factors to drive purchase decisions; hence consumers are revisiting their priorities before going for an upgrade.

The OnePlus 15 offers a larger battery, Qualcomm's latest chip, and interactive features for the water-friendly user. The Samsung S25 Ultra keeps its ground due to the high-res display, stylus compatibility, and the longest software support in the Android realm.

The OnePlus 15 might be the phone of choice for folks wanting a high-end device with better waterproof and wet-screen usability.

The OnePlus 15 is both IP68 and IP69 certified which means it can bear high-pressure water exposure and even immersion. This practically translates into real-life use: the phone's display still responds properly even if a few water drops cover it.

When it comes to the Galaxy S25 Ultra, which has only IP68, it would not be able to endure in such conditions. Display issues such as false tapping commonly occur on the devices from both Samsung and Apple when wet, which in turn will make it hard to perform functions like texting or switching songs. However, in the case of the OnePlus display, it will still be responding making it a reliable option for situations near a pool, during a rain shower, or even in a bathroom setup.

OnePlus particularly emphasizes its Sand Storm edition which comes with a MAO-treated frame, that can be regarded as a tougher build for daily usage.

The OnePlus 15 has 7,300mAh(approx) of battery power with a higher silicon ratio in the anode, thus gaining the most out of the battery. In fact, during days filled with GPS, shooting, messaging and social media, the phone usually still retains a considerable charge by evening.

The Galaxy S25 Ultra can benefit from its 5,000 mAh battery power and last until the end of the day, but heavy users usually need to recharge it sooner. OnePlus 15 users often watch their screen time go past nine hours without even getting close to the end of the battery. Charging is another thing the two brands have different approaches to, with OnePlus offering 80W wired charging and Samsung 45W.

The OnePlus 15 is powered by Qualcomm’s Snapdragon 8 Elite Gen 5 chipset. It is a good choice for gaming and high-load apps while the base price remains at $899.

The S25 Ultra was a $1,299 Samsung product but current Black Friday offers have reduced the price briefly to $899. If not for sale weeks, OnePlus is still the affordable option if high-performance under $1,000 is the requirement.

Reasons users may prefer the Samsung Galaxy S25 Ultra

Higher-grade display

Samsung’s current QHD AMOLED panel with an anti-reflective coating continues to be a leader in the industry. The latter allows for better viewing in direct sunlight and indoors as well. The S25 Ultra is still among the best screens for reading, browsing, and video watching in terms of consistency.

The OnePlus 15 also has a large, bright panel with a high refresh rate but its resolution and lack of anti-reflective technology hold it back from providing as good display comfort as Samsung.

Stylus support

The S Pen is still Samsung’s unique selling point. While the company this year took away some Bluetooth functions for the stylus, it still acts as a support for note-taking, sketching, and quick annotations.

OnePlus does not even give a similar stylus feature, thereby Samsung becomes the only premium choice for users that are dependent on pen input.

Longer software update lifespan

Samsung is the supplier of seven-year OS and security updates. For buyers who keep their phones for a long time, the above adds one extra year beyond what OnePlus offers.

The OnePlus 15 comes with Android 16 out of the box and guarantees four OS upgrades along with five years of security updates. Therefore, Samsung's wider update period not only makes the S25 Ultra more secure but also gives it a longer lifespan.

Core specifications summary

The OnePlus 15 is equipped with a 6.78-inch AMOLED display that can refresh up to 165Hz and has a maximum brightness of 1,800 nits. Samsung's Galaxy S25 Ultra is fitted with a 6.9-inch QHD AMOLED display that supports a refresh rate of up to 120Hz and has a maximum brightness of 2,600 nits.

Their weights are similar, with OnePlus being the lighter one with a weight ranging from 211g to 215g depending on the variant, and Samsung being slightly heavier at 218g.

Qualcomm processors are used in both phones, but OnePlus opts for the latest Snapdragon 8 Elite Gen 5 while Samsung employs the modified Snapdragon 8 Elite for Galaxy. Storage on the OnePlus is offered in two sizes of 256GB and 512GB, while the Galaxy has a third much larger option of 1TB.

The battery size difference is definitely the major factor that distinguishes them: OnePlus has it 7,300mAh rated with 80W wired and 50W wireless charging support, Samsung has it 5,000mAh rated with 45W wired and 15W wireless charging support. The camera systems diverge too; the OnePlus functions using three sensors of 50MP each and a front camera of 32MP, while Samsung does it with a 200MP main sensor and two telephoto, a 50MP ultrawide, and a 12MP selfie camera.

The configurations determine the prices that vary, but the OnePlus is $899 for the base model, while the Sumsung is always $1,299 unless there are discounts.