Q: No service on iphone 6s after update? Please help!

Did you already try the troubleshooting mentioned in this article?

If you can't connect to a cellular network or cellular data - Apple Support

Can you try to put in a different or new SIM card from your carrier?

If this does not work either, you'll have to get the phone checked by Apple or an Authorized Apple Service Provider next to your place.

iPhone - Contact Support - Apple Support

Find an Apple Authorized Service Provider

Hello

Mine also iPhone 6s after iOS 9.3.1 update starts shows as no service tried all possible methods

still stutuation same frustrated using other mobile for temporarily .

any one has solution for this ??

My son just solved my problem - for the last week, every time I would come home, my iPhone 6s would suddenly say no service but all other iPhones and computers in the house showed Wi-Fi without problems.

I have AT&T so wifi calling is an option, enabling this fixed my problem.

Settings > Phone > Wi-Fi Calling > Enable "Wi-Fi Calling on this iPhone" > Enter Emergency Address > When you exit emergency address screen, Wi-Fi calling should now be turned on.

It might take a few minutes to enable, then status bar should show Wi-Fi instead of "No Service".

Hope this helps