Fewer iPhone users are upgrading to iOS 26 than iOS 18

The iOS 26 update has the second-worst adoption rate of all iOS releases since 2015, falling behind both iOS 18 and iOS 8.

Though all eyes might be on iOS 27 and its AI-infused Siri, which debuted at WWDC, the software has only entered beta testing.

Most iPhones, or 79% of all devices to be more precise, are currently running iOS 26. This is according to Apple’s App Store data for June 2026, which also revealed that 86% of all devices introduced in the last four years have iOS 26 installed.

While these figures might seem impressive when taken at face value, the iOS 26 adoption rate is actually worse than that of the preceding iOS 18 update. In June 2025, 82% of all iPhones ran iOS 18, more than the 79% currently running iOS 26.

When taking into account Apple’s App Store data from all iOS releases from 2015 through 2026, the iOS 26 update actually has the second-lowest adoption rate, with only iOS 17 seeing fewer user upgrades.

The exact adoption rates for iOS 8 through iOS 26 for all compatible iPhones are the following:

• 2015 iOS 8: 84%
• 2016 iOS 9: 84%
• 2017 iOS 10: 86%
• 2018 iOS 11: 81%
• 2019 iOS 12: 88%
• 2020 iOS 13: 81%
• 2021 iOS 14: 85%
• 2022 iOS 15: 82%
• 2023 iOS 16: 81%
• 2024 iOS 17: 77%
• 2025 iOS 18: 82%
• 2025 iOS 26 79%

Note that all of these adoption rates were taken in June of the corresponding year, with the exception of iOS 12 usage data, which was published in August 2019.

At 79%, the iOS 26 adoption rate is below the 82.3% average from 2015 through 2026. Still, it’s not all bad news.

In February 2026, only 66% of all iPhones were running iOS 26, meaning more users have upgraded in the last couple of months. This is to be expected, though.

Even so, not everyone has embraced the controversial iOS 26 upgrade. According to Apple’s June 2026 App Store data, 14% of devices are still running iOS 18, while 7% are still on even older releases.

Apple’s data on newer devices running iOS 26

Since 2020, in June of every year, Apple has published iOS adoption rates for devices “released in the last four years.” At 86%, the adoption rate for iOS 26 is identical to that of iOS 17 in 2024. Meanwhile, iOS 18 had a higher score, at 88%.

The adoption rate of iOS 26 is also lower than the 87.6% average when Apple’s data from 2019 through 2026 is taken into account. Previous iOS updates, like iOS 12 in August 2019, saw lower adoption rates among newer devices, so iOS 26 is not an outlier in any sense.

Apple’s exact numbers for “all devices introduced in the last four years,” since the company released such data, are:

• 2019 iOS 12: 85%
• 2020 iOS 13: 92%
• 2021 iOS 14: 90%
• 2022 iOS 15: 89%
• 2023 iOS 16: 90%
• 2024 iOS 17: 86%
• 2025 iOS 18: 88%
• 2026 iOS 26: 86%

While iOS 26 has fallen behind iOS 18, possibly due to its Liquid Glass design language, the difference is likely not enough to cause alarm for Apple. Looking ahead, iOS 27 could boost iOS adoption rates.

Rather than controversial design changes, Apple says the iOS 27 update will deliver improved performance on older iPhones, with app opening speeds now being 30% faster, relative to previous releases.

Additionally, the same iPhone models that support iOS 26 can be updated to iOS 27, including the iPhone 11. As such, iOS 27 seems to have little to deter potential upgraders. Time will tell if the iOS 27 adoption rate will actually be higher than that of iOS 26, though.