Upgrade guide · updated 5 November 2026

Should I upgrade from the Canon EOS-1D X Mark III to the Canon EOS R3?

Verdict

Upgrading is likely worth it. Canon's EF-EOS R adapter gives full autofocus with EF and EF-S lenses, so your existing lenses carry over.

What you gain

  • 24.1MP instead of 20.1MP
  • faster bursts (30fps vs 16fps)
  • in-body stabilisation
  • a lighter body (1015g vs 1440g)
  • a mirrorless electronic viewfinder showing the exposure before you shoot, and modern subject-detection autofocus

What you give up

  • Nothing significant on paper

What it costs

EOS R3 newNo longer sold new
EOS R3 used (MPB, typical)£2,600
Your EOS-1D X Mark III trade-in (rough estimate)≈ £1,110
Net cost buying used≈ £1,490

Trade-in estimates assume about two-thirds of the typical MPB resale price; real offers vary with condition and shutter count.

Other upgrade paths

Frequently asked questions

Should I upgrade from the Canon EOS-1D X Mark III to the Canon EOS R3?

The upgrade is likely worth it. You gain 24.1MP instead of 20.1MP, faster bursts (30fps vs 16fps), in-body stabilisation, a lighter body (1015g vs 1440g).

How much does it cost to upgrade from the EOS-1D X Mark III to the EOS R3?

The EOS R3 costs No longer sold new new and about £2,600 used at MPB. Trading in a used EOS-1D X Mark III might bring roughly £1,110, so the net cost is around £1,490 buying used (a rough estimate: get quotes from MPB, Wex and Park Cameras).

Will my EOS-1D X Mark III lenses work on the EOS R3?

Canon's EF-EOS R adapter gives full autofocus with EF and EF-S lenses, so your existing lenses carry over.