A cartridge detachably mountable to a mounting portion in a main assembly of an electrophotographic image forming apparatus, includes: a cartridge electrical contact supplying electric power to a process device and being electrically connectable to a main assembly electrical contact when the cartridge is mounted to the mounting portion; first and second portions to be guided by a main assembly guide to guide the cartridge to the mounting portion when the cartridge is mounted to the mounting portion; and a guide portion guiding the main assembly electrical contact to the cartridge electrical contact when the cartridge is mounted to the mounting portion. The guide portion is disposed between the first and second portions to be guided, and the cartridge electrical contact is upstream of the guide portion with respect to a direction in which the cartridge is mounted to the mounting portion.