Part / accessory · Canon

Canon Mount Adapter EF-EOS R

verified 2026-10-07 Specs from Canon USA Mount Adapter EF-EOS R. Also known as: mount adapter ef-eos r, ef-eos r adapter, ef-eos r.

Specs

typeadapter
adapts fromlens-mount:canon-ef
adapts tolens-mount:canon-rf
also adaptslens-mount:canon-ef-s
excludesRF, EF-M and CN-E (EF cinema) lenses

Fits

  • lens mount Canon RF mount
    Canon EOS R mirrorless lens mount; full-frame and APS-C EOS R bodies all use it.

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Good to know
  • RF-S (APS-C) lenses mount on full-frame EOS R bodies, which automatically switch to 1.6x crop mode.
  • EF and EF-S lenses only work on RF bodies through a Canon Mount Adapter EF-EOS R (or the Control Ring / Drop-In Filter versions); they do not mount directly.
  • EF-M lenses and CN-E cinema lenses cannot be used via the EF-EOS R adapter.
  • EOS R50 excludes the RF 5.2mm F2.8L DUAL FISHEYE lens.

What does the Canon Mount Adapter EF-EOS R work with?

6 models in the graph.

  • Canon EOS R10 OEM awaiting review
    Needed to use EF/EF-S lenses; does not adapt EF-M or CN-E lenses.
  • Canon EOS R5 OEM verified
    Needed to use EF/EF-S lenses; does not adapt EF-M or CN-E lenses.
  • Canon EOS R50 OEM verified
    Needed to use EF/EF-S lenses; does not adapt EF-M or CN-E lenses.
  • Canon EOS R6 Mark II OEM verified
    Needed to use EF/EF-S lenses; does not adapt EF-M or CN-E lenses.
  • Canon EOS R7 OEM verified
    Needed to use EF/EF-S lenses; does not adapt EF-M or CN-E lenses.
  • Canon EOS R8 OEM verified
    Needed to use EF/EF-S lenses; does not adapt EF-M or CN-E lenses.

Informational only. Confirm with the manufacturer before buying or installing. Spotted a mistake? Report it.