The UV/visible absorption spectrum of CH3OCl has been measured at wavelengths between 200 and 460 nm and used to calculate photodissociation lifetimes in the stratosphere. At zenith angles between 80¿ and 90¿ and at a pressure of 100 mbar the lifetime with respect to photodissociation is of the order of 4 hours. The possible fate of CH3OCl in the stratosphere is discussed and analogies are drawn with HOCl. ¿ American Geophysical Union 1994