The Garmin Forerunner 255S might lack the extra splash of colour you get on the AMOLED-packing Forerunner 265, but this is still a great running watch for runners getting more serious about putting in more focused time on the treadmill, trails or pavement.
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Garmin has a sports watch at pretty much every price point and if you’re a runner who’s started to get more serious about that running time, the Forerunner 255S is a watch built for you.
The follow-up to the Forerunner 245 grabs Garmin’s new multiband GNSS mode from its top-end watches to improve outdoor tracking accuracy in typically challenging conditions along with offering two case sizes and is still something swimmers, cyclists and now triathletes can put to good tracking use.
It has since been succeeded by the Forerunner 265, which most notably adds an AMOLED screen into the mix, but with the 255S offering a similar feature set outside of that AMOLED for less, it’s still a running watch worth casting an eye over.
Design & build
1.1-inch transflective display
Waterproof up to 50 metres
The Forerunner 255S is the smaller of the two case options the 255 is available in, with a 41mm-sized case as opposed to a 46mm one. So if you like the idea of a watch that doesn’t dominate on the wrist, then this is the 255 model for you.
You can also grab the 255S in music or non-music editions. The former adds a built-in 32GB music player to store your own purchased audio or offline playlists from music streaming services including Spotify and Deezer. Opting for the music edition does push the price up by $50/£50.
That 41mm case is made from polymer, which is pretty much the go-to material for Garmin’s Forerunner watches and that’s matched up with an 18mm silicone strap that’s well built for exercise and can be removed if you want something more stylish or colourful in its place.
Along with a typical array of physical buttons there’s a 1.1-inch, 218 x 218 resolution memory in pixel (MIP) display. That’s a smaller display than found on the 245 and also a drop in resolution.
That does mean it lacks the more vibrant and colourful AMOLED you’ll find on the new Forerunner 265 and it’s not a touchscreen display either. If you’re happy living without that AMOLED touchscreen, then you’re still getting a good-sized screen here with solid viewing angles indoors and outdoors that was also fine to view during pool swims.
On the swimming front, it carries the same waterproof rating as its predecessor so it can be submerged in water up to 50 metres deep and you don’t have to take it off when taking a shower, though it’s worth taking it off every now and then to clean the sweat off the strap.
Turn the watch over and you’ll find Garmin’s own optical sensor that provides heart rate data continuously and during exercise and additionally offers blood oxygen measurements during sleep or throughout the day. That’s also where you’ll find the charging port, which is the spot for Garmin’s pretty universal charging cable for most of its watches though it lacks the wireless charging support Garmin introduced to its Vivomove Trend hybrid smartwatch.
Overall, it’s been a very comfortable time wearing the 255S. Yes, it’s small, but it’s light and unobtrusive and has a good enough display to soak up your metrics and other insights it serves up on the move.
Health and fitness tracking
HRV Status delves deeper into recovery
Improved GPS performance
Now includes open water swim tracking
Forerunner might be in the name, but like other Forerunner watches, the 255S also has the sensors and tracking features to track swimming, cycling and has profiles for hiking, skiing and snowboarding among other more outdoorsy pursuits.
Garmin has bolstered the sports profiles available with the 255S now getting an open water swimming mode and a dedicated triathlon mode to make it a more affordable triathlon watch in Garmin’s collection.
If you are turning to it for running, then there’s plenty here. It covers running profiles for ultras and track running, and you have access to Garmin Coach to sync workouts from programs built for 5K up to half marathon distance. There’s also a visual race predictor to give you a sense of what you might end up running on race day based on workout history.
The big additions here in this department are Garmin’s new multi-band GNSS mode and SATIQ technology. The first of those is similar to the dual band mode used on the Apple Watch Ultra, tapping into multiple frequency bands from supported satellite systems to deliver richer accuracy, particularly when near tall buildings, trees and mountain ranges.
Using multi-band GNSS means sacrificing more battery than using the standard GPS tracking mode, but does notably deliver more accurate data and did when we compared data to a non-dual band running watch running near big buildings, which can typically impact on location tracking accuracy.
The SATIQ technology is used by Garmin to automatically determine which level of satellite support you should use given your surroundings and location. So the idea is that you’re not wasting battery using the top end positioning mode when you don’t need it. Ultimately though, I found that manually picking the GPS mode was the best way to go in most scenarios.
Garmin has also sought to offer more in terms of insights into your recovery and also doing a better job of packaging your data in a way that you can better absorb it. On the analysis front, you now have something called HRV status, which uses heart rate variability measurements taken from the optical sensor during sleep. As the watch gathers those measurements over a few weeks it tries to better understand if your body is handling your current training load.
While a tap of the top physical button will reveal if your HRV status is good or bad, the presentation of it feels a touch complex. It would have definitely benefited from including the Training Readiness feature, which is available on the new Forerunner 265 and other pricier Garmin watches. It takes that HRV status and other pieces of your tracking data to give you a more simplified way of knowing whether you should train or ease off.
It’s something that I like about the new Morning Report, which you’ll see when you wake up telling you how you’ve slept, the weather forecast, suggested workouts to do for the day and a little motivational message to put some pep in your step. It feels a bit gimmicky, but it’s a feature I’ve warmed to over time and it’s quite a useful thing to look at first thing when you wake up.
On top of those new features, the 255S has everything the 245 offered. Whether that’s tracking daily activity and sleep or dishing out stress and blood oxygen saturation data, it can be useful as a fitness tracker and a monitor for your general wellbeing, but lacks the more serious health monitoring features you’ll find on the smartwatches like the Apple Watch and Samsung Galaxy Watch.
The heart rate monitor performed pretty well both for steady paced and more high intensity workouts against Garmin’s own HRM Pro Plus heart rate monitor chest strap, with scope to pair up an external heart rate monitor to bolster accuracy.
The 255S still lacks the full mapping support you’ll get on Garmin’s top-end Forerunner, Fenix and Epix watches, but it does offer point-to-point navigation and the ability to see breadcrumb trails in real time, which still makes it handy to get around or get back home if you’ve got a bit lost.
The Forerunner 255S’s sports tracking is well-rounded, offering good accuracy, a rich level of training analysis and some new features that do make it more reliable and insightful on those fronts too.
Spotify offline playlist syncing
Safety and live tracking features
Works with Garmin Pay
As a smartwatch, the 255S does a pretty admirable job of being useful when you’re not out tracking exercise. It works with Android and iOS and the experience of using the Garmin Connect companion phone app across those platforms is pretty consistent in terms of presentation and reliability of setup, pairing and syncing the watch.
In terms of smartwatch features, it’s the very same ones included on the 245. You have access to Garmin’s Connect IQ Store, which isn’t at Apple App Store level of quality in terms of apps, but is a useful place for grabbing some additional watch faces, data fields and extra widgets if a little slow at times to download and sync them over.
Viewing notifications works well in spite of that small screen, though it would be a nicer experience with the added touchscreen functionality you get on the Forerunner 265. If you’re using it with an Android phone, you can respond to texts and the notifications (out of luck on iPhone) and the support in general is better than you’ll find on most sports watches.
Garmin Pay is supported here too, letting you make contactless payments from the watch if your bank is supported and it worked fine for me when I needed to quickly grab a drink. But it does lack the slickness and supported banks you get from rival watch-based payment systems.
Then you have the music features, which is made up of the controls you can use for controlling audio playing on your phone and the built-in music player to store purchased audio and playlists from Spotify, Deezer and Amazon Music.
There’s capacity to store up to about 500 songs and getting playlists over from supported music streaming services can be done in a relatively straightforward fashion. Using the music streaming during tracking dents the battery more, but the support works well, it was easy to pair a bunch of different Bluetooth headphones to use it.
Again, it would be nice to have a touchscreen here to interact with the music features, but if you want the ability to stream music, podcasts and audiobooks on a sports watch, you want a Garmin like the 255s on your wrist.
Battery life and charging
Up to 12 days in smartwatch mode
Up to 26 hours in GPS mode
Up to 5.5 hours with music streaming
The Garmin Forerunner 255S is a watch I’d say is built to last a good week if you’re planning to use its key sports tracking and smartwatch features on a regular basis throughout that week. Garmin says it should be 12 days, but getting to that number means lighter use of core tracking modes. Such longevity is helped by the MIP screen rather than a power-hungry AMOLED.
The biggest drain on battery life here is the music streaming and the continuous blood oxygen saturation monitoring, which sees the battery life drop quite dramatically. If you can live without that 24/7 blood oxygen data, then it’s worth disabling it.
If you switch to the new multiband GNSSS outdoor tracking mode, that number drops from 26 hours to 13 hours to give you a sense of the difference in battery usage. Add music streaming into the mix and that drops to 5.5 hours. That’s still good enough to last a long marathon, but listening to music does hit the battery hard.
The numbers are bigger than what was promised on the Forerunner 245, but unlike a lot of more expensive Garmin watches, you’re getting something here that will hold out for a week with the potential to go further if you sacrifice some of those more battery-hungry features.
Price and availability
The Garmin Forerunner 255S costs $349.99/£299.99 or $399.99/£349.99 for the music version. You can buy it direct from Garmin.
The 255S definitely sits at that more midrange category of sports watches, so it’s a fair bit of a jump from Garmin’s entry level watches like the Forerunner 55 ($199.99/£149.99) and the likes of the Coros Pace 2 ($199.99/£179.99), which does offer a similar feature set for less money.
It does also share similar features to the Forerunner 265, which sees roughly a $100/£100 price jump compared to the 255S to get that added AMOLED display and some of Garmin’s latest software features.
The Garmin Forerunner 255S might not be the newest model in this particular Forerunner range, but that doesn’t mean you should entirely discount buying it either.
If you’re not that fussed about having an AMOLED touchscreen display and features like Training Readiness and a few extra sports profiles and would gladly take a bigger battery instead, then there’s still reasons to go for the 255S.
It offers a really comprehensive experience overall and not just for runners either. If you were looking for a Garmin watch that can work as a triathlon watch, then it’s worth looking at too.
The problem Garmin has is that the Coros Pace 2 can offer a lot of what the 255S offers for less money. It’s not a better smartwatch and the UI won’t be everyone’s cup of tea, but for sports tracking and value, it’s up there with the 255.
The Garmin Forerunner 255S offers a great experience overall, that’s not as pricey as the newer 265 and shows going for an older watch isn’t necessarily a bad thing.