The song was played on a number of shows in 1996, this recording (from 'MiniDiscs [HACKED]') is from March 27th at The Fillmore in San Francisco, and was the first live appearance of the song:
The band also performed 'I Promise' during the august 1996 US dates, when they played in support of Alanis Morissette. This video comes from august 14th 1996:
To this day, this version from August 27th 1996 in Pittsburgh (also from 'MiniDiscs [HACKED]') is the last known public performance of 'I Promise':
Radiohead recorded 'I Promise' during the OK Computer sessions. This version, that according to Thom sounds a bit like Joy Division, has been released in 2017 on the OKNOTOK 20th anniversary edition of OK Computer.
The latest available recording of this song is a soundcheck from september 8th 1997: