The song was played on a number of shows in 1996, this recording is from march 29th at The Wiltern in Los Angeles:
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 26th 1996 in Hershey 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: