Samsung Galaxy S25 Ultra vs iPhone 16 Pro Max: battery life

Battery life is one of the biggest differences between premium smartphones, especially for people who use their handset for navigation, streaming, photography, work and constant 5G connectivity. The Samsung Galaxy S25 Ultra and iPhone 16 Pro Max are both built for heavy daily use, yet they approach endurance, charging and power management in different ways.

Samsung equips the Galaxy S25 Ultra with a 5,000mAh battery, while Apple’s iPhone 16 Pro Max has a smaller cell but benefits from highly integrated hardware and software. On paper, capacity gives Samsung an advantage, although Apple publishes strong video-playback figures for its largest iPhone.

For Australian buyers, the practical result depends on network coverage, screen brightness, climate and charging habits. A commuter travelling between Parramatta and the Sydney CBD may see different results from someone driving long distances through regional Queensland, where a weak signal can drain a phone faster.

Battery capacity and manufacturer claims

The Galaxy S25 Ultra uses a 5,000mAh battery, continuing Samsung’s familiar Ultra-series capacity. Samsung rates it for up to 31 hours of video playback under controlled conditions. The phone also includes the Snapdragon 8 Elite for Galaxy processor, which is designed to deliver high performance while managing demanding workloads more efficiently than previous flagship chips.

Apple does not usually promote iPhone battery size, but the iPhone 16 Pro Max is reported to have a battery of roughly 4,685mAh. Apple claims up to 33 hours of video playback, up to 29 hours of streamed video and up to 105 hours of audio playback. These figures are impressive because the A18 Pro chip, display controller and iOS power management work closely together.

Manufacturer estimates are useful for spotting broad trends, but they should not be treated as a promise of everyday performance. Video stored on the phone, streamed content, gaming, camera use and mobile reception all produce different results.

Everyday endurance in Australia

In mixed daily use, both phones can comfortably reach the end of a normal working day. The Galaxy S25 Ultra tends to appeal to users who want a large battery reserve for navigation, hotspot use and long camera sessions. With moderate social media, messaging and video, it can often finish the day with a healthy percentage remaining.

The iPhone 16 Pro Max is similarly dependable, and its standby performance is particularly strong. People who put the phone down for several hours during work or sleep may find that it loses very little charge. iOS also tends to manage background activity conservatively, which helps preserve power when the device is not being actively used.

Extended 5G use changes the picture. In Melbourne’s CBD or around Sydney’s Central Station, a phone may move between crowded network cells and different bands throughout the day. That switching can increase consumption. The same applies in areas with patchy coverage, such as parts of the Blue Mountains or long stretches outside major regional centres.

Performance, display and heat

The Galaxy S25 Ultra has a 6.9-inch QHD+ AMOLED display with an adaptive refresh rate of up to 120Hz. It is bright, smooth and excellent for scrolling, gaming and watching sport, but a large high-resolution panel can consume considerable energy when used outdoors at high brightness.

The iPhone 16 Pro Max features a 6.9-inch Super Retina XDR OLED display with ProMotion up to 120Hz. Its resolution is lower than Samsung’s, although the difference is difficult to notice in ordinary use. Apple’s display efficiency and tightly controlled animations help the phone remain competitive even with a smaller battery.

Heat is an important factor in Australian conditions. A handset left on a car dashboard near Adelaide or used for navigation during a hot Perth afternoon can reduce performance and charge more slowly. Gaming, 4K video recording and hotspot use create additional heat on both devices. A case, direct sunlight and poor airflow can make the situation worse.

For intensive mobile gaming or long entertainment sessions, including browsing mobile gaming reviews, the Samsung’s larger capacity may provide extra breathing room. Neither phone should be judged solely by a short benchmark because sustained heat and network conditions have a greater effect on battery drain.

Charging speed and convenience

Samsung supports wired charging up to 45W with a compatible charger. It also offers wireless charging and reverse wireless charging, allowing the Galaxy S25 Ultra to top up accessories such as earbuds or a smartwatch. The 45W system is useful when a quick lunchtime charge is needed, although Samsung does not include a wall charger in the box.

The iPhone 16 Pro Max supports faster MagSafe charging than earlier models, reaching up to 25W with suitable equipment, while wired USB-C charging remains a convenient option. A compatible power adapter is required, and Apple also leaves the charger out of the retail package.

Samsung generally has the advantage in wired charging speed, particularly when the battery is low and the user has only a short time near a power point. Apple’s MagSafe ecosystem is more polished for people who prefer a cable-free desk or bedside setup. Wireless charging is convenient on both phones, but it produces more heat and is slower than a direct cable.

In Australia, USB-C compatibility is a practical benefit. The same cable can often serve a laptop, tablet, phone and power bank, reducing the number of accessories needed for travel. That matters for people flying from Brisbane to Perth or carrying several devices on a work trip.

Battery health and long-term ownership

Battery capacity gradually declines after repeated charging cycles, regardless of the brand. Apple provides detailed battery-health information in iOS, including maximum capacity and performance management options. This makes it easy to see when an ageing battery may be affecting daily endurance.

Samsung includes battery protection settings that can limit charging or control how the phone reaches 100 percent. Features such as adaptive charging are intended to reduce the amount of time the battery remains fully charged overnight. Using these settings may help preserve capacity over several years, though actual results vary with temperature and usage.

Software support also affects how long a phone feels efficient. Both the Galaxy S25 Ultra and iPhone 16 Pro Max are premium devices expected to receive extensive updates. A well-supported phone can remain useful for years, making battery replacement more worthwhile than replacing the entire handset.

Australia’s repair market should be considered before purchase. Battery replacement availability, labour costs and authorised service locations vary between cities. Buyers in Sydney, Melbourne and Brisbane usually have more options than those in smaller regional towns, so checking local support before spending flagship money is sensible.

Which flagship lasts longer?

The Galaxy S25 Ultra is the stronger choice for users who value battery capacity, rapid wired charging and a large reserve for navigation, gaming and mobile data. Its 5,000mAh cell gives it an obvious hardware advantage, and many users will appreciate the ability to recover a useful amount of charge quickly.

The iPhone 16 Pro Max remains a highly competitive endurance phone. Its efficient A18 Pro chip, strong standby management and well-optimised iOS experience can deliver a full day with room to spare. People already using Apple Watch, AirPods or MagSafe accessories may also prefer its charging ecosystem.

There is no universal winner in battery life. Heavy gaming, bright outdoor use and weak reception can reduce either phone to a similar result, while moderate use may allow both to last into a second day. The Samsung is better for charging speed and capacity; the iPhone is especially appealing for standby efficiency and consistent software management.

For Australian shoppers, network compatibility, warranty access and charging accessories deserve as much attention as laboratory figures. Read the detailed coverage from the Bahria Sports team, compare local pricing, and choose the phone that matches your daily routine rather than relying on battery capacity alone.

Check current Australian prices and trade-in offers before buying, then pair your chosen flagship with a quality USB-C charger, sensible battery protection settings and a case that does not trap excessive heat. That combination will help the Galaxy S25 Ultra or iPhone 16 Pro Max deliver dependable performance through workdays, commutes and weekend travel.