Canon Rumors published images of the rumored RF-S 10-18 f4.5-6.3 IS STM, an ultra-wide angle zoom lens with APS-C sensor coverage for Canon's RF mount cameras. From the images, we see that the lens has built-in IS , stepper motor and 49mm filter thread which is significantly smaller than the Canon EF-S 10-18mm f4.5-5.6 IS STM lens' 67mm filter thread (note that the latter have a slightly faster f5.6 aperture at 18mm compared to F6.3 of the RF-S lens).
This will be great news for the users of APS-C sensor RF cameras such as the EOS R7, EOS R10, EOS R50 and EOS R100 since the only wide angle lens option they currently have are the Canon RF 15-30mm F4.5-6.3 IS and Canon RF 15-35mm F2.8L IS USM full frame lenses which are not really wide in APS-C terms (24mm FF equivalent at wide end), and the recently announced RF 10-20mm F4 L IS STM full-frame lens (16mm FF equivalent at wide end) that sells for $2,299!
Price and Availabilty
The RF-S 10-18mm lens is expected to be released before the end of 2023, and no price info leaked yet,