In 2023, the time had come to replace my Apple Watch after years of neglecting my Series 4. I opted to sell it on Poshmark and started exploring more recent models that boasted features compelling enough to encourage regular use. I settled on the Series 8, even though the Series 9 had just launched, since I was purchasing two watches—one for myself and another for my mother. This decision has proven to be quite beneficial.

If you are in the market for a new smartwatch or contemplating an upgrade, it’s essential to know which earlier Apple Watch models still retain their functionality today. My Series 8 is performing exceptionally well three years post-release, and I strongly advocate for utilizing older gadgets as long as they remain useful. However, not every Apple Watch will maintain the same level of performance as the Series 8 in 2025.

Avoid Obsolete Models

A clear distinction must be made: seven of Apple’s smartwatch models are no longer receiving support, meaning they won’t benefit from software or security updates. This poses a risk of incompatibility with your iPhone or specific applications. Essentially, purchasing a watch that Apple no longer supports is unwise. The unsupported models include:

• Apple Watch Series 0
• Apple Watch Series 1
• Apple Watch Series 2
• Apple Watch Series 3
• Apple Watch Series 4
• Apple Watch Series 5
• Apple Watch SE (first generation)

Although the Series 6 is still supported, it is expected to be the next model to lose that status. When Apple unveils watchOS 26 next week, we’ll find out if it remains supported for another year. If it does not, it will permanently be limited to watchOS 11.

Advancements in Performance

There are several factors to consider regarding older Apple Watch models, extending beyond their ability to run the latest operating systems. Each new iteration has seen various enhancements. For instance, the Series 4 brought the ECG sensor, whereas the Series 6 introduced a blood oxygen sensor, which was later disabled for certain models due to legal issues. The Series 7 is known for its faster charging capability, a feature that has persisted in subsequent models (though not in the first-generation Apple Watch SE).

Generally, newer models exhibit improved speed. Apple routinely installs its latest S-Chip—the brain of the Apple Watch—into each new series, resulting in a faster and more efficient device. The Series 6 houses the S6 chip, the Series 7 contains the S7, and this trend continues up to the Ultra series (the original Ultra features an S8 chip akin to the Series 8, while the Ultra 2 is equipped with an S9 chip similar to the Series 9).

While all currently supported models share fundamental features—like physical activity tracking, sleep monitoring, and message notifications—each newer version boasts its unique advancements. Here’s a brief overview:

• The Series 7 offers rapid charging, a larger display, and enhanced durability.
• The Series 8 introduced temperature monitoring, crash detection, and a low-power mode for maximizing battery life (also found in the second-generation Apple Watch SE).
• The Series 9 features innovative gesture controls, on-device Siri access, improved locational accuracy, and a display that is twice as bright as its predecessor.
• The first-generation Apple Watch Ultra includes a robust titanium body, customizable app shortcuts, a depth gauge, enhanced GPS accuracy, a 36-hour battery life, and an emergency siren.
• The Apple Watch Ultra 2 boasts a display with a staggering maximum brightness of 3,000 nits along with media playback capability.
• The Series 10 showcases the largest screen available on an Apple Watch and offers accelerated charging.

If a particular feature stands out as essential, be prepared to invest in that specific watch model. Conversely, for standard functionalities, considering an older option may be prudent. For a clearer comparison of features among models, Apple’s comparison tool can be quite beneficial.

Battery Life Considerations

All technology, including the Apple Watch, experiences some level of degradation, particularly with its battery. While there are steps available to mitigate battery issues, over time, the lithium-ion cell powering the device will not perform as well as it initially did. This may become more significant than merely the watch’s ability to support a new operating system. Apple’s warranty does not cover batteries that diminish from normal usage, charging a fee of $99 for replacements, which could be better spent on upgrading to a new model. An exception exists: if you have AppleCare+ and your battery holds less than 80% of its original capacity, service is complimentary, but the watch must be taken to an Apple Store or authorized service provider for testing.

Recommendations for Purchase

Thoughtful consideration of the critical features in newer models is necessary before proceeding with a purchase, and staying with Series 7 or later is advisable. Although the Series 6 remains operational, it is only a matter of time before it becomes obsolete.

Overall, the performance of the Series 8 has exceeded expectations over the past two years. The touchscreen functions flawlessly, buttons respond optimally, and it syncs effortlessly with all applications and devices. It effectively tracks my steps and exercise intensity, which fulfills my needs perfectly. If a smartwatch is what you seek, older models that still support the latest operating systems should not be overlooked. Sourcing refurbished or second-hand versions can lead to substantial savings, allowing funds to be reserved for future technological advancements from Apple.

As Apple no longer sells models below the Series 10 or SE, exploring resale and refurbished markets is essential for acquiring Series 6, 7, 8, or 9. This approach can yield significant savings (for reference, a new Series 10 starts at $399, though discounts are often available, and a refurbished Series 8 recently cost me $219).