Best Smartwatches for Sleep Tracking

Choosing a smartwatch starts with understanding what will make the biggest difference in everyday use and which compromises are actually worth accepting.

Define what you want the purchase to help you achieve before comparing individual products.

Some watches focus heavily on ECG, sleep and wellness, while specialist sports watches devote more attention to training load, recovery, navigation and endurance performance.

Write down the three requirements that matter most and remove any option that fails one of them.

Include every essential accessory and supporting cost before deciding how much is available for the main product.

The Apple Watch Series 9 remains a strong refurbished and used buy for iPhone owners who want Apple's mature smartwatch experience without paying for the newest generation. Its S9 chip, bright 2,000-nit always-on display, 64GB storage, health sensors, fast charging and excellent iPhone integration still make it highly capable. However, buyers should compare the price carefully with the Series 10 because the newer model provides larger displays, a thinner case and additional water-related sensors. A Series 9 makes the most sense when it is meaningfully cheaper. Used buyers should check battery health, inspect the screen and case, confirm that Activation Lock has been removed and ensure that a compatible charging cable is included. It makes the most sense for iPhone owners wanting a highly integrated smartwatch. Its strongest reason to buy is the S9 SiP provides fast everyday performance and supports on-device Siri processing for selected requests. The main trade-off is typical battery life remains approximately 18 hours, meaning many users will need to charge the watch every day. We would look elsewhere if you use an Android phone.

The Apple Watch SE 2 remains one of the most sensible low-cost routes into the Apple Watch ecosystem, particularly when bought refurbished or used at a substantial discount. It retains the features most people actually use every day, including notifications, Apple Pay, fitness tracking, sleep tracking, heart-rate monitoring, Crash Detection, Fall Detection and optional cellular connectivity. Its main compromises are the lack of an always-on display, ECG, blood-oxygen sensing and temperature sensing. Buyers should compare its price carefully with discounted Series 8 and Series 9 models because a small increase in cost can unlock a much broader health and display feature set. Used buyers should check battery health, inspect the screen and case and confirm that Activation Lock has been removed. It makes the most sense for first-time Apple Watch buyers. Its strongest reason to buy is the SE 2 provides the core Apple Watch experience at a substantially lower price than premium Series and Ultra models. The main trade-off is the display is not always-on, so the screen normally needs a wrist raise or tap before information becomes visible.

The Apple Watch Series 10 remains a very capable choice for iPhone users, particularly when purchased refurbished or used at a meaningful discount. Its larger 42mm and 46mm wide-angle OLED displays, thin case, strong health and fitness features, fast charging and excellent iPhone integration make it a compelling everyday smartwatch. However, buyers should compare the price carefully against newer Apple Watch generations. If the difference is small, buying the newer model is likely to provide stronger long-term value. Used buyers should confirm battery condition, inspect the display and case carefully, check that Activation Lock has been removed and ensure that the included band and charger meet their needs. It makes the most sense for iPhone owners wanting a highly integrated everyday smartwatch. Its strongest reason to buy is the 42mm and 46mm case sizes provide larger displays than previous mainstream Apple Watch generations while retaining a relatively slim design. The main trade-off is typical battery life remains approximately 18 hours, meaning many users will still charge the watch every day.

Shortlist only the products whose strengths match your intended use and whose weaknesses you can comfortably accept.

Apple Watch Series 9 is a concrete alternative worth considering.

Apple Watch Series 8 is a concrete alternative worth considering. The Apple Watch Series 8 is now best treated as a used or refurbished value option for iPhone owners. Its always-on display, temperature sensor, ECG, blood-oxygen sensing, Crash Detection, fitness tracking and strong Apple ecosystem integration still provide a very complete smartwatch experience. However, buyers should compare its price closely with Series 9 and Series 10. The Series 8 becomes particularly attractive when it is substantially cheaper. Used buyers should inspect the screen and case, verify battery health where possible, confirm that Activation Lock has been removed and ensure that a compatible fast-charging cable is included.

Compare the obvious purchase with at least one cheaper route and one genuinely different alternative.

Paying for health sensors you will never use. ECG, temperature sensing and advanced wellness tools can increase price but may provide little value to buyers who mainly want notifications, workouts and basic sleep tracking.

Buying a smartwatch when a fitness tracker would be enough. People mainly interested in steps, sleep and basic health tracking may get longer battery life, lower weight and better value from a fitness tracker instead of a full smartwatch.

Before paying, check that the decision is based on your needs rather than popularity, urgency or a headline discount.

If it were our money, Apple Watch Series 9 would be the current starting point because the Apple Watch Series 9 remains a strong refurbished and used buy for iPhone owners who want Apple's mature smartwatch experience without paying for the newest generation. We would choose differently if typical battery life remains approximately 18 hours, meaning many users will need to charge the watch every day would interfere with the main use. We would only spend more when the additional cost removes a limitation we would genuinely notice.