UPDATE: The iPhone SE running iOS 10.2 can be jailbroken with Yalu. Click here for more information on Yalu.
The iPhone SE cannot be jailbroken at this time.Pangu Team released an iOS 9.1 jailbreak in March 2016. Because the iPhone SE ships with iOS 9.3 installed, it cannot be jailbroken using this tool.
While iOS 9.0 was jailbroken within a month of its initial launch, there is no timeline for a future jailbreak release. Developers are likely to wait until iOS 10.0 is available to introduce a new jailbreak.
Those with devices running firmware newer than iOS 9.1 have no option to jailbreak, and must remain with stock iOS for the time being.