Samsung’s Galaxy S8 went on sale in April 2017, but both it and consumers are always looking for the next best thing. Samsung has a reputation to keep, with its S-series flagship crowned best smartphone three years running. (Also see our Samsung Galaxy S8 and Galaxy S8+ reviews.)

Its Galaxy S series is renowned for combining premium design, the latest features and unbeatable performance, and we expect to see more of the same in 2018.

And so we look ahead to the Samsung Galaxy S9 and S9+, reportedly codenamed ‘Star’ and ’Star 2’, for which the rumours are already rolling in. As in previous iterations, we expect there will be two versions of the S9: a standard model with a 5.8in display, and a Plus model with a slightly larger 6.2in screen. Both will feature the dual-curved edge and Infinity display, but new to these phones will be the in-display fingerprint-scanning tech rumoured for the Galaxy S8.

Features were standardised across the line with the Galaxy S8 and S8+, so expect only minimal differences in those specifications affected by the larger screen, such as battery capacity (a larger case allows for a little more juice), dimensions and weight. As such, the rumours you read in this article will be applicable to either handset.

Samsung is said to have begun working on the Galaxy S9 back in March 2017, but it's even further ahead than we imagined. We're amazed to discover that what is thought to be the Galaxy S9 with a Snapdragon 845 processor has been spotted on Geekbench as early as July 2017. 

More Samsung rumours: Galaxy S8 mini Galaxy S8 Active | Galaxy Note 8 | Bixby speaker

When is the Galaxy S9 release date?

Expected release date: March 2018 announcement, April 2018 on sale

Speculating over Samsung Galaxy release dates used to be easy, with the S series unveiled during an Unpacked press conference a day ahead of MWC, traditionally held in late February or early March, and the Note series in a second Unpacked conference the day before IFA at the beginning of September.

In the past couple of years Samsung has mixed things up, announcing the Galaxy Note 5 in August 2015 and the Note 7 in August 2016, both ahead of IFA. Then, in 2017, it announced the Galaxy S8 and S8+ in March, some time after February’s MWC tradeshow. The phones eventually went on sale at the end of April.

The early Note announcements have allowed Samsung to get out slightly ahead of key rival Apple with its September iPhone announcements. And though it has never officially confirmed what was the hold up for this year’s Galaxy S8, we’d put our money on a combination of extra safety checks in light of the Note 7 battery explosions and some strategic planning given that Samsung had the exclusive on the Snapdragon 835, this year’s flagship phone processor of choice.

Since Samsung helped Qualcomm to build the 835, it was agreed that no other phone using that processor could go on sale before the Galaxy S8. Key rival LG was forced to opt for the Snapdragon 821 in its G6, while HTC and Sony pushed back their U11 and Xperia XZ Premium launches so far that consumers lost interest.

It’s a strategy that played out well for Samsung in 2017, and by moving its main product launch away from the fanfare of MWC it removed a lot of the noise that was detracting from Galaxy S8 hype. We think it could adopt a similar approach in 2018, announcing the Galaxy S9 and Galaxy S9+ in March, with an on sale date of April 2018.

After all, the company is reportedly already in talks with Qualcomm about helping it build the Snapdragon 845. Could we see the same exclusive deal set up for 2018’s flagship phone processor?

For what it’s worth MWC 2018 will be held from 26 February to 1 March, so the earliest we will see a Samsung Galaxy S9 announcement is Sunday 25 February 2018.

How much will the Galaxy S9 cost in the UK?

The Galaxy S8 and S8+ were Samsung’s most expensive S-series phones yet at £689 and £779 respectively. Part of this extra cost can be attributed to the new features, but finances following both Brexit and the Note 7 disaster have almost certainly come into play here, too.

Until this year, Samsung always kept its pricing reasonably constant, and in line with other flagship phone makers. For that reason we’d be surprised to see the price go any higher than the current RRP.

It’s always worth considering with Samsung phones that - more so than with any other manufacturer’s smartphones - SIM-free prices fall rapidly in the few months following launch. As an example, just a couple of months after the Galaxy S8 announcement you can pick one up for £579 from Amazon, a saving of £110.

Also see: Best phones 2017 and Best Android phones 2017

What are the rumoured new features and specifications of the Galaxy S9?

Samsung reportedly began working on the Galaxy S9 in late March 2017, which would mean it is already six months ahead of schedule compared to where it was with the Galaxy S8 and S8+ last year.  And that means more time for quality control, more time for building in new features and, hopefully, more happy customers.

Amazingly, in July 2017 an early version of the alleged Galaxy S9 was spotted in the Geekbench database - that's some seven or eight months before we expect to see the phone announcement. A device with the model name SM-G9650 is listed with a 1.78GHz quad-core Snapdragon 845 processor and just 4GB of RAM. It scored 7371 points in the RenderScript test, which is lower than the Galaxy S8 managed in the same test. There are no performance scores.

Rumoured specifications Samsung Galaxy S9 Samsung Galaxy S9+
Price £689 £779
Operating system Android O 8.0 with TouchWiz Android O 8.0 with TouchWiz
Processor Qualcomm Snapdragon 845 (Exynos 9810 UK) Qualcomm Snapdragon 845 (Exynos 9810 UK)
GPU Adreno 550 Adreno 550
RAM 6GB LPDDR4 6GB LPDDR4
Storage 64GB with microSD support 64GB with microSD support
Display 5.8in (2960x1440, 570ppi, 18.5:9) Super AMOLED 6.2in (2960x1440, 529ppi, 18.5:9) Super AMOLED
Fingerprint scanner In-display In-display
Ports USB-C USB-C
Audio Stereo speakers Stereo speakers
Camera 12Mp dual-lens 12Mp dual-lens
Battery Circa-3000mAh, Adaptive Fast Charging (wired & wireless) Circa-3500mAh, Adaptive Fast Charging (wired & wireless)
Waterproofing IP68 IP68
Extra features Heart-rate sensor, Bixby AI Heart-rate sensor, Bixby AI

Screen

An unnamed source suggests the first work on the Galaxy S9 began with the screen, and that there is not expected to be any change with the sizing: so we’ll see a 5.8in Galaxy S9 and 6.2in Galaxy S9+.

The Bell reports that Samsung has already ordered these screens from suppliers, but with one key difference: they will feature the in-display fingerprint-scanning tech that was rumoured for but never made it into the final spec of the Galaxy S8.

We’d expect to see the same 2960x1440, 570ppi, Super AMOLED ‘Infinity’ panel on the S9, and another 529ppi panel on the S9+. Given that Samsung by default limits the screen resolution to Full-HD+ (2220x1080) in the Galaxy S8, we really don’t think it will push up the resolution up to 4K.

It is possible that despite keeping the same dimensions and resolution the display technology itself could be improved. Samsung is reportedly using screen tech codenamed ‘Sunflower’ for the Galaxy S9 - it’s still Super AMOLED, but should improve display fidelity and be more consistent and reliable.

The new virtually full-screen 18.5:9 ratio will also likely remain, as will features such as the always-on display and edge functionality.

In 2016 Samsung patented a glass-coating technology that helps water to bounce off the screen, making it much easier to use in the rain. This tech could well be introduced in the Galaxy S9, which will itself most likely be waterproof. (The Galaxy S8 is rated IP68, which means it is resistant to submersion up to a depth of 1.5m for up to 30 minutes.)

Processor

According to Aju Business Daily, Samsung is in talks with Qualcomm to help it build the Snapdragon 845, which could be the chipset onboard 2018’s Galaxy S9, plus other flagships. However, it says Taiwan’s TSMC is in the running as well as Samsung (TSMC is responsible for Apple’s A11, another 10nm chip).

The 10nm Snapdragon 835 Samsung helped Qualcomm to manufacture was 27 percent faster and 40 percent more energy-efficient than the company’s previous 14nm chips. The upcoming Snapdragon 845 is said to be built on the 7nm manufacturing process, and will be even faster and more efficient than ever.

(The nm figure relates to the distance between transistors, and the more you can squeeze on to a chip the faster it will be.)

Despite holding the exclusive on the Snapdragon 835, in the UK the Galaxy S8 and S8+ are sold with Samsung’s own Exynos 8895. It’s rumoured that the UK variants of the Galaxy S9 and S9+ will come with an 8nm Exynos processor, possibly the 9810.

Storage and RAM

You get 64GB of storage as standard with the Galaxy S8, along with microSD support. That’s already quite generous, so we’re not expecting to see any changes here.

Something we might see in the Galaxy S9, though, is for Samsung to finally push up the RAM allocation from 4GB to 6GB. This is by no means out of the question, with some phones that are now a year old offering this amount of memory. It would also help it in its quest for ever-increasing performance.

Battery

It is doubtful that we will see much difference in battery capacity for the Galaxy S9, given that the size of the phone is not expected to change - you can only cram in what you can cram in, and Samsung will want to be careful following the Note 7.

Fast charging - both wired and wireless - will likely feature, though we suspect Samsung will continue to use its own Adaptive Fast Charging tech rather than the Quick Charge built into Snapdragon processors.

Camera

Samsung traditionally leads the pack when it comes to new smartphone features, so we’re somewhat puzzled by the fact it has yet to introduce a dual-camera. Nevertheless, one is tipped for the upcoming Note 8, and if that happens expect it to feature in the Galaxy S9 too.

Samsung’s Note 8 is thought to be getting a 12Mp dual-lens camera with OIS and 3x optical zoom. We’ll know more in August when that phone is unveiled.

Ports and connections

Samsung introduced USB-C rather than Micro-USB for the Galaxy S8, though it didn’t follow the likes of Apple in removing the 3.5mm headphone jack and relying on wireless or USB-C audio. There is a danger it could take that plunge this time around, though nothing has yet been confirmed.

Fingerprint scanner

One change we would like to see in the design, and something we hope Samsung will take into account following significant consumer criticism, is the awkward placing of the rear fingerprint scanner. It’s not so much being on the back of the handset that offends us, but how it is wedged in beside the camera as if it were an afterthought.

The Galaxy S9 could be the phone in which we finally see the fingerprint scanner built into the screen glass itself. Qualcomm has announced Qualcomm Fingerprint Sensors, a new ultrasonic technology that allows fingerprint-sensing tech to be built directly into a phone’s OLED screen. It also works in glass and aluminium.

Less revolutionary alternatives might include the scanner taking a more central position below the primary camera, or Samsung taking a leaf out of Sony’s book by building it into the power button on the edge. Or maybe Samsung will go all in with iris scanning. To be fair, any of these options would be preferable to what we have now.

Software

We’re expecting the final version of Android O to be revealed in September or October 2017, with the next version - Android P - not due until the same time next year, well after the Galaxy S8’s anticipated announcement. It’s therefore almost certainly the OS you’ll find onboard the S9 and S9+, albeit with the TouchWiz UI on top.

Samsung also introduced the Bixby AI assistant in the Galaxy S8, which we would have thought would have only got more intelligent for the Galaxy S9.

Design

It is way too early for leaked images of the Galaxy S9 and S9+ (the main image shown on this article is of the Galaxy S8 Plus), though we will publish them here as soon as we spot them.

Read next: Best new phones coming in 2017

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