He was employed as a musician by Sir Edward Seymour, Earl Hertford (1539–1621) and accompanied him on a diplomatic visit to Brussels in 1605.
Bartlet's only publication was A Booke of Ayres with a Triplicitie of Musicke, published in 1606.
He describes himself as a "Gentleman and Practitioner in this art," claiming a connection to a coat of arms.
Although A Book of Ayres is described by Peter Warlock as containing "a good deal of very commonplace stuff," many of his musical settings work very well, especially the homorhythmic madrigal-like settings.
Bartlet's music was widely popular in its time, appearing in many later manuscripts and prints.