The company hasn't changed the design much compared to last year's device, but there are a couple of differences, including a new camera and a more ergonomically positioned fingerprint scanner.
We've reviewed both, we've lived with both and if you're trying to decide which to buy or if you should upgrade, here's how the Samsung Galaxy S9+ compares to the Samsung Galaxy S8+.
Best Samsung Galaxy S8+ deals
Samsung Galaxy S9+ vs Galaxy S8+: Design
- Both IP68 water and dust resistant
- Dual camera on the S9+
- S9+ heavier but slightly narrower and shorter
The Samsung Galaxy S9+ and Galaxy S8+ both feature a glass front and rear with a metal core and they are both IP68 water and dust resistant.
From the front, nothing has changed, with the curved Infinity display being the highlight on both devices for a look that's difficult to tell apart.
But there is a small difference in their rear design. The Galaxy S9+ has a vertically-aligned dual-rear camera situated in the centre at the top with the fingerprint sensor below it. The Galaxy S8+ meanwhile, has a single-lens camera with a fingerprint sensor positioned awkwardly to the right. In real terms, the new layout is easier to use than the S8+.
There isn't much difference in terms of physical size, though the S9+ is a little heavier. The newer device measures 158.1 x 73.8 x 8.5mm and weighs 189g, while the S8+ measures 159.5 x 73.4 x 8.1mm and weighs 173g. In reality, about the only difference is the colours offered.
Samsung Galaxy S9+ vs Galaxy S8+: Display
- Both 6.2-inches, 2960 x 1440 pixels, 529ppi
- Both curved Super AMOLED
- Both 18.5:9 aspect ratio
The Samsung Galaxy S9+ and the Galaxy S8+ both feature a 6.2-inch curved Super AMOLED display so the colours will be bright and punchy on both devices. The Galaxy S9+ however is a newer generation of display, so it's brighter and overall a better performer, although you probably won't notice much difference to day-to-day use.
They also both offer a Quad HD+ resolution - 2960 x 1440 pixels - which puts both their pixel densities at 529ppi, meaning they should also offer the same result in terms of image sharpness. However, to save battery life, both devices revert to a Full HD+ resolution, with the top settings being a manual adjustment if you want it.
Both the Galaxy S9+ and S8+ have an aspect ratios of 18.5:9 for that taller and not too wide look and they both support HDR content, to make the most of Netflix, for example. Between the two, there's little to choose.
Samsung Galaxy S9+ vs Galaxy S8+: Hardware
- S9+: Exynos 9810 or Snapdragon 845, 6GB RAM, 128GB storage, microSD
- S8+: Exynos 8895 or Snapdragon 835, 4GB RAM, 64GB storage, microSD
- Both have 3500mAh battery
- Both have 3.5mm headphone jack
- Massive difference in speaker quality
Both these phones come in two different variants, one equipped with Qualcomm Snapdragon, the other with Samsung's own Exynos hardware. The performance is pretty much the same and you'll likely not have the choice of chipset - you'll just have to buy the model for your region. For the UK, that's Exynos.
The Galaxy S9+ has a Qualcomm Snapdragon 845 or Exynos 9810, is supported by 6GB of RAM and 128GB of storage, and it offers microSD support for storage expansion up to 400GB.
The Galaxy S8+ features the Exynos 8895 or Snapdragon 835, coupled with 4GB of RAM and 64GB of storage so the new device does offer an upgrade in hardware, as you would expect. The S8+ has microSD support too though.
In performance terms, the newer model is faster and offers more graphics power, although it's not a huge change. All the hardware versions have the sample 10nm core architecture and for general tasks all are smooth and fast.
Both the S9+ and the S8+ have a 3500mAh battery, compatible with fast charging and fast wireless charging and they both have a 3.5mm headphone jack. The battery life on both devices will get you through the day, but they aren't class-leading. Equally, there's little difference between the overall battery life of the two devices.
On the speaker front, however, there's a huge difference. The Galaxy S8+ speaker is generally weak and flat. The Galaxy S9+ speaker is infinitely better, offering Dolby Atmos enhancement, AKG tuning, real volume and detail. If you use the speakers a lot, then the S9+ is the obvious choice.
Samsung Galaxy S9+ vs Galaxy S8+: Camera
- Galaxy S9+: Dual aperture, Dual Pixel 12MP camera with 2x optical zoom
- Galaxy S8+: Dual Pixel 12MP camera
The Samsung Galaxy S9+ features a dual camera. The camera is made up of a wide-angle Super Speed Dual Pixel 12-megapixel autofocus sensor with dual aperture of f/1.5 or f/2.4, adjusting automatically to suit the shooting conditions. In addition there's a 12-megapixel telephoto lens with an aperture of f/2.4.
The dual camera offers dual optical image stabilisation and it allows for 2x optical zoom, as found on the Galaxy Note 8, but the S9+ also offers super slow motion video at 960fps and automatic motion detection, like the standard S9. It's a good performer, offering loads of functions, fast to use and focus, although it's not quite as capable in HDR capture as some leading rivals, like the Google Pixel 2, but it's great at low light photos.
The Galaxy S8+ meanwhile has a single 12-megapixel Dual Pixel rear camera with autofocus, optical image stabilisation and an aperture of f/1.7. It offers slow motion video but not super slow motion and it has 8x digital zoom but no optical zoom. In terms of the hardware, it's a less capable and slower camera, with lesser low light performance.
Both the Galaxy S9+ and the Galaxy S8+ have an 8-megapixel front-facing camera with an aperture of f/1.7 and autofocus and are very much the same. The big difference, in reality, is the 2x optical zoom - the dual aperture is clever, but we're not convinced its advantages are worth choosing the S9+ over the S8+ - but the zoom is.
Samsung Galaxy S9+ vs Galaxy S8+: Software
- Android Oreo and Samsung Experience UX
- Galaxy S8 has been slow to upgrade
The Oreo update is currently being pushed out to S8 and S8+ devices, but Samsung has been generally slow to bring the latest version of Android to these phones.
There will be a couple of differences between these two devices in some areas, such as the camera, but the feel is very much the same thanks to the Samsung Experience UX that both phones run. The Galaxy S9+ introduced personalised AR emoji, but we're not sure this is a reason to buy the S9+ alone.
Generally speaking, once the S8+ has received the update in your region, the experience on the software front will be very much the same.
Samsung Galaxy S9+ vs Galaxy S8+: Price
The Samsung Galaxy S9+ costs £869 SIM free and is now widely available. It's an expensive device, but there are a range of competitive deals to make it more affordable for contract customers. But in wider market terms, the Samsung Galaxy S9+ is one of the most expensive devices you can currently buy.
The Galaxy S8+ cost £779 when it first launched, but it is now available for around £699 (Samsung RRP), making it significantly cheaper than the S9+. That price brings it down to a level that undercuts or rivals a lot of flagship alternatives. You get a lot of phone for your money.
Samsung Galaxy S9+ vs Galaxy S8+: Conclusion
- Galaxy S9+ offers more power
- Galaxy S9+ offers a better camera
- Galaxy S8+ is a more appealing price
The Samsung Galaxy S9+ makes several improvements on the Galaxy S8+, as many will have expected. It offers more RAM, more storage, a faster chipset and improvements to the camera, as well as the fingerprint sensor position, but the design, display and overall software experience of these two phones is very much the same.
The fingerprint scanner is better placed on the S9+, but that's not a huge factor. The bump in power makes for more competitive running of demanding games - like PUBG Mobile for example - while the camera's low light performance is boosted and the 2x optical zoom gives you something that the Galaxy S8+ can't match - and the speaker performance is much better too. If you can get a good deal, then pick the Samsung Galaxy S9+.
If you're looking to upgrade from the Galaxy S8+, then the S9+ doesn't make such a great case for itself. The feel is the same, a lot of the day-to-day performance feels the same. Ultimately, if you've already got the S8+ then you'll be paying more for only a minor set of grades.