Garmin Instinct 3 Solar review | Is this the toughest hiking watch around?

The Garmin conveyer belt continues to rumble on as the brand releases a third generation of its rugged Instinct watches. Is the new Garmin Instinct 3 one of the best hiking watches around? Here’s everything you need to know.

Garmin Instinct 2 Solar vs Garmin Instinct 3 Solar: What are the differences?

Last year the Garmin Instinct 2 Solar won our 'Best Value' award in our round-up of the best GPS running watches. Is it worth paying more for the Garmin Instinct 3 or should you stick with the Instinct 2?

You can read my full review of the Garmin Instinct 2 Solar for more on that watch, but let’s recap on the headlines. Through extensive testing, I found the Garmin Instinct 2 Solar 45mm (now priced at £299.99) to be a "a great all-rounder of a smartwatch – a rugged, super-tough, versatile outdoor watch that will appeal to multi-sports adventurers". It was well-priced, rugged, protective, lightweight (only 54g) and compact.

But there were negatives. The screen was under-sized and diminutive (only 23mm), with a very basic, monochrome, underwhelming screen. You didn’t get dual-frequency GPS, the 30-hour battery life was okay, but not amazing, and the solar charging was somewhat redundant in the cloudy UK.

It never felt like a running watch either – it was more of a generalised adventure or hiking watch. Yet overall I was impressed, awarding the Garmin Instinct 2 Solar a 'Best Value' award.

This leads us to the important question. How does the Garmin Instinct 3 Solar 45mm differ and, crucially, is it any better than the Instinct 2? Let’s deep-dive into the details.

Screen tweaks

The headline change is that the Garmin Instinct 3 range now features an AMOLED version. This is only available in a non-solar option, costing £389.99 (45mm). Sadly, I haven’t got my hands on this version (I only have the regular Instinct 3 Solar), so I can’t judge how effectively this upgrade has been executed. However I imagine that the AMOLED screen will be a big improvement.

A common criticism of the Instinct 2 range is that the screen is too small, basic, monochrome and, ultimately, not the best at displaying information. Conversely the full-colour AMOLED version should be much brighter and more vibrant, with a higher 390x390 pixel resolution (compared to 176x176 in the Instinct 2).

This is likely to be most noticeable in the 50mm version of the Instinct 3, with a wider screen for the display of information. The downside of an AMOLED screen, however, is that it costs much more (£429.99, 50mm version), and it will drain the battery faster (you get eight hours less from the Instinct 3 AMOLED 45mm in GPS-only mode compared to the Instinct 3 Solar 45mm version, for example).

So it’s a mix of pros and cons – is it worth it? We’ll get to that later.

New features

There are a few other key changes between the Garmin Instinct 2 and Garmin Instinct 3 ranges. The Garmin Instinct 3 now has an integrated flashlight, which – according to Garmin – "enhances utility, making it more versatile in outdoor and low-light conditions".

Some tech-y adventurers will probably enjoy this feature, but how much will you actually use it? If you often have a head torch or phone nearby, a smartwatch flashlight may be a totally redundant feature. On the other hand, perhaps you’ll use it often. It probably comes down to personal preference.

The Instinct 3 also features expanded health and wellness features and tracking, including heart rate variability (HRV) status and women’s health tracking for menstrual cycle and pregnancy insights. Again, in my eyes rather niche and specialist improvements, rather than game-changers, but some users may benefit from them.

Solar charging

Garmin also states that the Instinct 3 range has a "larger, more efficient solar lens which harnesses the power of the sun even better".

The brand states the following example: compared to the Instinct 2 Solar, the new 50mm Instinct 3 Solar gets more than five times the battery life in GPS mode when solar charging.

But perhaps a better comparison is a like-for-like evaluation of the Garmin Instinct 2 Solar 45mm and Garmin Instinct 3 Solar 45mm. In GPS-only mode with solar charging, the newer model provides 130 hours of battery, compared to the Instinct 2’s measly 48 hours. In max battery GPS mode with solar charging, the new model upgrades the battery life from 370 hours to unlimited.

In my opinion, this definitely sounds like a positive, worthwhile upgrade – however there is a big caveat. All of this assumes 50,000 lux conditions, which you won’t always get. In the past I’ve found that the benefits of solar charging are negated quite considerably when you’re hiking in cloudy, grey conditions, so that’s something worth remembering.

Weight and GPS

There are a few other changes I’ve noticed between the Instinct 2 and 3, which aren’t overtly highlighted by Garmin. The Instinct 3 Solar 45mm is 2g lighter than the Instinct 2 Solar 45mm, clocking in at 52g instead of 54g.

You also get multi-band frequency with the Instinct 3, but don’t with the Instinct 2. As the name suggests, this multi-band system uses multiple frequency bands and ensures "more consistent tracklogs and improved positioning when using the device in challenging environments", as Garmin explains.

This means "the receiver tracks more than one radio signal from each satellite on different frequencies, which can reduce errors caused by environmental interference" such as trees, mountains and buildings. Ultimately this should improve the GPS accuracy of the Instinct 3 compared to the 2.

Design and pricing

One thing that hasn’t changed, however, is the rugged design, which is broadly similar between the 2 and 3.

Blimey, that took a while. So let’s get down to the crucial question: is it worth paying extra for the Instinct 3 instead of the Instinct 2?

My opinion is quite clear. The differences between the Instinct 3 Solar 45mm and Instinct 2 Solar 45mm are only minor upgrades and updates, rather than wholesale changes. The design and ethos of the watches are very similar, and you only really get tweaks rather than game-changing improvements.

The additions of note are the flashlight, multi-band GPS and improved solar charging – but are these worth paying £349.99, instead of £299.99? If you can afford it, it’s probably worth it.

But some of the upgrades seem a little redundant (personally I never use a watch flashlight), and I’m a little dubious about how useful solar charging is in grey, dreary weather (like you often get in the UK, for example).

In my eyes, a better all-round option might be to wait for the Instinct 2 Solar price to plummet and then grab yourself a steal.

However, if you’re interested in the AMOLED version, then in my opinion that screen change is a big, game-changing upgrade, making the Instinct 3 a whole different proposition.

Personally I love an AMOLED screen and, most likely, the Instinct 3 AMOLED 45mm will offer a far brighter, more vivid user experience than anything the Instinct 2 range can offer.

Now, let's get stuck into our full Garmin Instinct 3 review, shall we?

Design, screen and user interface

The Garmin Instinct 3 Solar has a simple, no-nonsense design, both internally and externally. It’s not an all-singing, all-dancing watch, but it’s not trying to be. It has a rugged, robust, chunky design with a military-like look to it.

It’s definitely strong and bombproof, and gives you the impression you could throw it off a cliff-top and it’d be fine. Garmin describes the design as "rugged... including a 0.9-inch (23mm) display, 45mm metal-reinforced bezel and scratch-resistant display”.

Despite the rugged chunkiness, the Instinct 3 comes in a dinky package, with a compact, minimalist size. The hardware includes two buttons on the right-hand side and three on the left for option selection and user interface navigation, without the need for a touchscreen.

On the subject of the screen, it’s 23mm wide, which is rather small and underwhelming. A nice touch is the dual-screen design, with an additional circular window in the top right corner of the display.

But overall the screen’s pixel resolution (176x176) and non-colour display (it’s a monochrome MIP ‘memory-in-pixel’ screen), are slightly disappointing for £300.

I guess the screen approach will please those who prefer practical simplicity, as well as battery life, but in 2025 the Instinct 3’s screen seems rather outdated and boring, in my opinion. If you think similarly, then you’ll be far better served by the AMOLED version.

GPS accuracy and battery life

For most uses, the Garmin Instinct 3 delivers adequately accurate GPS tracking, ensuring your activities are measured precisely. As with all GPS watches, this works far better in maximum accuracy mode, with 'all satellite systems and multi-band' activated.

This is the mode you should always use, in my eyes, unless you’re taking on a multi-day, hardcore adventure with no means of charging the watch each night (but with a half-decent power bank you should be able to do this, even if you’re off-grid).

The 'max battery' mode will significantly prolong battery life, but in my experience this ruins the GPS accuracy. I once used a watch in one of these modes during a 100-mile ultra and it over-tracked the distance by some 20km or so, which clearly was too big an error to be useful to me.

Depending on which mode you use, the battery life will alter significantly. Generally speaking I’ve found the battery life adequate, if not spectacular, and for simple runs or hikes it’s more than powerful enough. Here are the official details.

The Garmin Instinct 3 Solar 45mm offers varying battery life depending on usage modes, with solar charging capabilities enhancing performance:

It’s worth noting that the solar charging stats assume all-day wear with three hours per day outside in 50,000 lux conditions.

Weight and size

On my scales the Garmin Instinct 3 Solar 45mm weights just 52g, which is 2g lighter than the Garmin Instinct 2 Solar 45mm. This definitely classes as ultralight and a big weight saving compared to other popular watches.

The Suunto Race, for example, weighs 83g and the Garmin Fenix 7 Pro Sapphire Solar 47mm weighs 75g. But the Instinct 3 can’t compete with the ultralight Coros Pace 3, which is a minimalist 39g.

The Garmin Instinct 3 Solar is designed to be both tough and compact. With a bezel size of 45x45x14.9mm, it maintains a sleek profile without being bulky. As a result, it comfortably fits wrists with circumferences ranging from 137-204mm, staying securely in place even during high-speed movement, such as running.

Water resistance

The Garmin Instinct 3 Solar has a 10ATM rating, which means it can withstand pressures equivalent to a depth of 100m under water. It is suitable for swimming, therefore.

Navigation and mapping

In my opinion this is not really a watch designed for navigation and mapping. It does have mapping functionality, but it’s very basic - you only get non-contoured, breadcrumb-style navigation (no real mapping), very sparse details and the screen is so small you can’t really see anything.

It’s infinitely inferior to the kind of mapping you get on Garmin’s premium watches, such as the Fenix range or some of the higher-end Forerunner series. These watches have excellent, super-functional mapping. If that’s what you want or need from a watch, the Instinct 3 Solar is not for you. Instead you’ll need to save up a bit more and look at the Fenix range.

Verdict

A versatile, rugged, well-designed multi-sports watch with a functional, fuss-free approach – but the screen is arguably too basic and you don’t get 'proper' mapping.

For watches with more of a nod toward running, take a look at our list of the best GPS running watches.

About the author

James Forrest is a prolific peak bagger and long-distance walker who’s one of the most high-profile outdoor writers in the UK. He writes regular features and route guides for Trail and has been one of our main gear testers for the last few years.

James is based on the edge of the Lake District so when he isn’t off on his latest crazy adventure or challenge, he’s walking in his local fells. James reviews every type of outdoor kit for Trail and is a real authority on everything you need for wild camping and packing light for a multi-day walk.