A lens apparatus is attachable to and detachable from an image capturing apparatus and configured to communicate with the image capturing apparatus. An accessory is attachable to and detachable from the lens apparatus and configured to communicate with the lens apparatus. The lens apparatus includes a determiner configured to determine whether update data is used for the lens apparatus or the accessory, the update data being transmittable from the image capturing apparatus and used to update stored data stored in the lens apparatus or the accessory, and a controller configured to transmit the update data to the accessory received from the image capturing apparatus when the determiner determines that the update data is used for the accessory.