Apple Stops Signing iOS 15.3.1 Following iOS 15.4 Release, Downgrading No Longer Possible - MacRumorsOpen MenuShow RoundupsShow Forums menuVisit ForumsOpen Sidebar
Skip to Content

Apple Stops Signing iOS 15.3.1 Following iOS 15.4 Release, Downgrading No Longer Possible

Following the release of iOS 15.4 on March 14, Apple has stopped signing iOS 15.3.1, the previously available version of iOS that came out in February. As iOS 15.3.1 is no longer being signed, it is not possible to downgrade to that version of iOS if you've updated to iOS 15.4.

iOS 15
Apple routinely stops signing older versions of software updates after new releases come out in order to encourage customers to keep their operating systems up to date, so it is not unusual that iOS 15.3.1 is no longer being signed.

iOS 15.3.1 was a bug fix update that addressed WebKit vulnerabilities, while iOS 15.4 was a major update that added new emoji characters, Face ID with a mask support, and tons of other features. Apple has also stopped signing tvOS 15.3.

Popular Stories

iPhone 18 Pro and Pro Max Feature

'Apple Upgrade' Program Reportedly Launching Next Week

Tuesday July 21, 2026 8:30 am PDT by
Apple and Klarna are partnering on a new "Apple Upgrade" leasing program set to launch in the U.S. on Tuesday, July 28, according to Bloomberg's Mark Gurman. The program will allow you to finance most iPhone, iPad, Mac, and Apple Watch models, with a 24-month term for iPhones and Apple Watches and a 36-month term for iPads and Macs. Customers will be able to pay off the device early during...
iPhone 18 Pro Deep Red Feature

iPhone 18 Pro Launching in Two Months With These 12 New Features

Tuesday July 21, 2026 6:22 am PDT by
It is now mid-July, and that means the iPhone 18 Pro and iPhone 18 Pro Max are now just two months away. The devices are expected to look similar to the iPhone 17 Pro and iPhone 17 Pro Max, but there will still be many year-over-year changes, with rumored features including a smaller Dynamic Island, 5G via satellite, and more. Apple is expected to unveil the iPhone 18 Pro, iPhone 18 Pro Max, ...
iPhone 18 Pro Deep Red Feature

iPhone 18 Pro Launching in Two Months With These 12 New Features

Friday July 17, 2026 10:39 am PDT by
It is now mid-July, and that means the iPhone 18 Pro and iPhone 18 Pro Max are now just two months away. The devices are expected to look similar to the iPhone 17 Pro and iPhone 17 Pro Max, but there will still be many year-over-year changes, with rumored features including a smaller Dynamic Island, 5G via satellite, and more. Apple is expected to unveil the iPhone 18 Pro, iPhone 18 Pro Max, ...

Top Rated Comments

Black Magic Avatar
57 months ago

I'm still on iOS 14, but it looks like I need to upgrade since a policy at work requires I am on iOS 15 in order to use the internal Wi-Fi. I am going to try to hold out for iOS 15.5.1 though.
You holding out for what? You denying yourself great features thinking you are saving yourself from bugs and headaches? You like 2 years behind the curve and you feel like that is something to brag about?
Score: 9 Votes (Like | Disagree)
Y014951 Avatar
57 months ago

What features am I missing out on exactly that are so detrimental? I have been doing this every year since iOS 11. At the end of the day, it’s about the apps. iOS is just an OS. Most of what I already need in terms of integration doesn’t require iOS 15.
I honestly don't understand the downvotes. Mr. Dee seems to be a quite active participant in the Macrumors forums so I believe he knows what features he's missing. It's his decision to update his devices (or not) after all...
Score: 7 Votes (Like | Disagree)
Black Magic Avatar
57 months ago

What features am I missing out on exactly that are so detrimental? I have been doing this every year since iOS 11. At the end of the day, it’s about the apps. iOS is just an OS. Most of what I already need in terms of integration doesn’t require iOS 15.
Your employer is trying to nudge you into the present. You are obviously missing the point.
Score: 5 Votes (Like | Disagree)
canadianreader Avatar
57 months ago
We need the right to downgrade. I hope sideloading will open that door.
Score: 4 Votes (Like | Disagree)
57 months ago
and good riddance
Score: 4 Votes (Like | Disagree)
MysteriousStain Avatar
57 months ago
I am also still on 14 because it is stable and I got tired of updating and getting bugs and battery drain. I’ve heard complaining about 15.4 so I’m still waiting for something solid.
Score: 3 Votes (Like | Disagree)