How do I update my iPhone 6 to iOS 15.1?

You cannot update an iPhone 6 – the phone you asked about – past iOS 12. If this is the phone you have, it is very out of date, and if you want to run modern apps, it is long past time to replace it.

About iOS 12 Updates - Apple Support

iPhone - Apple

You can update an iPhone 6s – the phone shown in your equipment line – to the latest release of iOS 15, currently iOS 15.8.3.. Apple no longer offers updates to iOS 15.1, specifically.

About iOS 15 Updates - Apple Support

Update your iPhone or iPad - Apple Support

Dandal22 wrote:

i updated my whatapp iphone 6 but looking for ios 15.1 how to update ios 15.1 in iphone 6

[Re-Titled by Moderator]

That is NOT possible. iPhone 6 can be updated to iOS 12.5.7 and NO higher. You have an 11 year old, obsolete iPhone, which had a good life, but it is now too old and lacks the hardware required to be updated further. Time to retire your old phone and buy a new one.

An iPhone 5s, iPhone 6, or iPhone 6 Plus isn't capable of 13 or above; they require at least 2GB of RAM.

(259621)

Do you have an iPhone 6 or an iPhone 6s Plus.....(shown in your profile)?

The current version of iOS 15 is iOS 15.8.3 if you have an iPhone 6s Plus.

You can’t!I think you should get a new phone you can buy a very cheap refurbished iPhone SE or iPhone 11, but using a iPhone 6 in 2025 isn’t practical