Microsoft says it will support Windows RT for at least four years

The original Apple iPad no longer receives iOS updates after just 2 1/2 years. So that makes the 4 1/2 years that Microsoft has promised to support Windows RT seem like a long time. The Microsoft product support lifecycle page actually shows that the Redmond based company will continue to support the platform through April 11th 2017. That means Microsoft Surface RT owners can expect to receive firmware updates through that date. Microsoft normally offers 5 years of  mainstream support to consumer and business users of Windows  and business users receive an extended 5 years. But because the Microsoft Surface RT combines software and hardware, it is considered different than just software. Office Home and Student 2013 RT will have the same support policy as Windows RT.

"For Surface devices, any Surface software installed, embedded or downloaded on the device is subject to the software lifecycle support policy for that software (unlike other HW devices such as Xbox) ... The hardware support lifecycle policy applies only to the Surface hardware (and as stated above not the Surface software). For Surface devices, that policy affects only the tablet device and hardware based accessories (and for example not to soft goods accessories such as cases)."-Microsoft product support lifecycle site

What about support for Windows RT tablets produced by other companies? Microsoft has not indication of support length for non-Surface Windows RT tablets on its lifecycle site, but does say that it will reveal other information related to the software "as available."

source: Microsoft

Microsoft Surface RT will be supported through April 17th, 2017