Which Apple Watch should you buy? Is the top-of-the-range Series 5 worth its premium price tag, or should you save money and compromise on the Series 3? Which model, size, case material, colour and strap is best for your needs and budget? With dozens of combinations available, the choice can be overwhelming.

In our Apple Watch buying guide, updated for winter/spring 2020, we explain all the options, and help you decide which model is right for you and where to get the best price.

Where can you buy an Apple Watch?

You can pick up both the Watch Series 5 and Series 3 direct from Apple. Prices start at £199/$199 and top out at £1,399/$1,350 for the luxury models.

You can also buy the Apple Watches from third-party retailers, including John Lewis, Currys and Very. These sellers may still offer models which Apple itself has stopped selling, such as the Series 4, although stock is likely to be limited.

For the latest third-party offers worth your consideration, check our roundup of the best Apple Watch deals.

You've also got the option of picking up refurbished models from Apple's Refurb Store. We take a look into whether you should buy a refurbished Apple Watch separately.

The current range

Apple has discontinued the original Apple Watch, Series 1, Series 2 and Series 4. You can currently choose from various versions of the Series 3 and Series 5.

There are (from cheapest to most expensive) aluminium, stainless steel, titanium and ceramic versions of the Series 5, and numerous colour finishes and straps available for both the 3 and 5 - including Nike's sporty straps and fashion straps from Hermes. There are two screen sizes for each model, and you can also choose whether you want to pay extra for cellular connectivity, or if you're happy with GPS only.

Here's the Series 3 line-up, together with links to buy on the Apple Store:

Material Strap 38mm, GPS 42mm, GPS 38mm, cellular 42mm, cellular Buy link Aluminium Sport Band £199/$199 £229/$229 £299/$299 £329/$329 Apple Store Aluminium Nike Sport Band £199/$199 £229/$229 £299/$299 £329/$329 Apple Store

And here are the prices for the Series 5:

With all these combinations to choose from, it's tricky to know where to start.

Series 3 vs Series 5

The first big decision is whether you want to pay substantially more for the new and redesigned Series 5 model, or if you want to save money and settle for the Series 3.

There's no denying that £199/$199 is an appealing price tag, but our advice would be to go for the 5 if you can possibly afford it, as you'll get the accumulated benefits of two generations' worth of upgrades. The Series 3 is also less future-proofed, and will stop getting watchOS software updates sooner.

The 5 offers screens that are 30% larger than those of the Series 3, but it's slimmer too; overall the volume of the new models is lower. They also have a redesigned Digital Crown, which gives haptic 'click' feedback for more accurate scrolling, an improved speaker (which is 50% louder), a repositioned microphone for better call quality and better cellular reception.

Unlike any previous Apple Watch model, the Series 5 has an always-on display. You still wake it up with a tap or by raising your wrist, but even when 'asleep' it shows a dimmed, simplified and less frequently refreshed version of your watch face. Our reviewer found this feature so well executed that he turned off raise-to-wake.

Battery life on both the 3 and 5 remains poorer than those of some rival (and less fully featured) watches, but it's impressive that Apple has kept it roughly the same on the 5, despite the additional drain of that always-on screen. This is thanks to an ultra-low-power display driver, a new power management integrated circuit and some other upgrades.

The Series 5 has an S5 processor chip which appears to be largely the same as 2018's S4, but even so it will comfortably outperform the Series 3's S3 - Apple says it's twice as fast. And wireless should be faster too, because of the newer W3 chip replacing the W2.

The Series 5 also gets a compass, and finally it offers a raft of health-related features unavailable to Series 3 buyers: ECG, improved heart sensor, fall detection.

That's a whistle-stop tour of the main differences, but we compare the two models in more depth in our Apple Watch Series 5 vs Series 3 comparison article.

Do I need cellular?

The next big choice is between a standard GPS watch and the more expensive cellular model, which uses an electronic SIM card to be able to make phone calls and get online independently of your iPhone. As well as the higher initial price, you'll have additional running costs for data usage and network fees.

Whether you opt for the regular or cellular (GPS or GPS + cellular to use Apple's terms) mostly depends on your likely usage. If you're always likely to have both your iPhone and Watch on you at the same time, you really won't see any benefit from the cellular connectivity, so it won't be worth the cost.

However, if you like the idea of being able to leave your phone at home and still take calls and check emails - when you're exercising, for example - then you could benefit from cellular.

Special editions

The Apple Watch Nike+ and Apple Watch Hermès have the same internals and specifications as the standard models, but distinct aesthetic appearances.

The Apple Watch Nike+, which is made from aluminium, is aimed at those who love running and are looking for a sport-oriented smartwatch.

The Hermès is made with stainless steel, with fancy straps and an Hermès stamp on the back. The various versions look lovely but start at more than £1,000. Note that these are only available with cellular.

Upgrading from the Series 4, Series 2 or older models

We've compared the Series 3 and 5, but if you've still got a Series 0 (ie the original model), 1 or 2 the new releases will look like a truly dramatic improvement.

Our experience suggests that at this point the original Apple Watch is basically obsolete: all the copies we own have slowed down drastically. To give an idea of the differences in speed between the older generations, we tried turning them off and seeing how long they take to power on again:

Starting from the very first model, here are the highlights of what each model added to the formula:

'Series 0' (2015): Officially just called Apple Watch, or 'first gen'. The original: where it all began.

Series 1 (2016): Essentially a rebadged version of the original. But it added a faster processor.

Series 2 (2016): A beloved upgrade. Increased battery life and screen brightness, and added GPS and better waterproofing. And a still faster processor.

Series 3 (2017): One big new (optional) feature: cellular connectivity. And an even faster processor.

Series 4 (2018): Bigger screen, thinner body, more sophisticated heart sensors and fall detection. And the fastest processor yet.

Series 5 (2019): Always-on display, compass, extra onboard storage. New S5 processor appears to offer the same performance as 2018's S4, although power-management improvements help with battery life

As you'll appreciate, moving up more than one step at once means you get multiple sets of advantages.

Going from Series 2 to Series 5, for instance, means you'll be getting the option of cellular for the first time as well as the new design and ECG feature, and the always-on display and compass. Upgrading from Series 1 adds GPS and a better screen.

What about the Series 4?

The Series 4 is an odd one - unlike the rest of these discontinued models it isn't particularly old. It came out in 2018 and is newer, unsurprisingly, than the still-available Series 3.

Personally we would advise against upgrading from Series 4 to 5, since they are so similar in terms of design and performance. The exception would be if you're totally blown away by the always-on screen, but that was by far the most significant upgrade for 2019.

We look into this decision in great depth here: Apple Watch Series 5 vs Series 4.

Should you buy the large or small size?

The Series 3 comes in two sizes of case: 38mm or 42mm. The Series 5 is 40mm or 44mm.

The general interpretation is that these are designed to suit an average woman and an average man's hand/wrist dimensions respectively, but you needn't feel bound by that: there are no other changes to the design of the watch other than size - no explicitly masculine/feminine decorative elements etc. (Also, a man can wear a 'woman's watch' if he wants to. Don't let anyone tell you different!)

The measurements represent the (approximate) height of the watch face, in millimetres. That's a bit odd, because when categorising sizes of smart devices we usually refer to the size of the screen, measured diagonally from corner to corner, in inches. (The iPhone 5s is a '4in smartphone', for instance.) But Apple seems to have decided to do things differently for this product category.

Weight varies according to the material, size and whether or not cellular is included.

The size of a wearable is a crucial, critical factor, and because of this, we would recommend that you postpone the buying decision until you can be sure which size is right for you. That might mean buying in store rather than ordering online; if you can get to an Apple Store or a reasonably well-appointed reseller then they will have watches in stock that you can try on before buying.

Finally, bear in mind that the available configurations of material/colour/strap are slightly different depending on the size - so your choice in this category will slightly reduce your options in others. We strongly recommend that you prioritise size above other considerations, however. Don't be like the shoe shopper who goes one size too big because they're 90 percent off - the pain isn't worth it!

Which colour do you want?

The material used determines what colour you can find the Apple Watch in.

Aluminium: silver, gold, Space Grey

Stainless steel: plain, gold, Space Black

Titanium: plain, Space Black

Ceramic: white

The colour, unlike the material, doesn't affect the price, so pick whichever version you like best. But your choices will depend on your choice of model and material.

The Series 3 comes in aluminium only, and this has to be either silver or Space Grey - not much choice there. But the Series 5 offers all the material and colour options listed above.

Docks, stands and chargers

The Apple Watch comes with a small, basic charger, but you may wish to buy an additional dock that allows you to charge overnight while also displaying the time. For our picks, see our roundup of the best Apple Watch stands and chargers.