The mission, part of a wider NATO operation, is designed to deter potential Russian aggression.
Personnel from 121 Expeditionary Air Wing have been based at Mihail Kogalniceanu Air Base, near the Black Sea Coast, while supporting efforts to protect the skies above Romania.
Since deploying in April, the RAF Typhoon jet force launched nine times against suspect aircraft.
The Quick Reaction Alert scramble responsibility has now been passed to six CF-188 Hornets, the sixth time Canada has taken on the role.
It also marks the end of the RAF's third deployment on Operation Biloxi, after previous Black Sea patrols in 2017 and 2018.
Patrols were only a fraction of the RAF's deployment, however.
Watch: How RAF Typhoons have been policing the skies over Romania.
121 Expeditionary Air Wing also supported exercises with both land and naval forces, training with the UK Carrier Strike Group when the formation was in the Mediterranean this year.
In June, the force took part in a unique joint training scramble with German and Romanian aircraft.
Seven RAF personnel were presented with the Romanian Air Force Emblem of Honour by the Chief of the Romanian Air Force Staff, representing a mission completed to an impeccable standard.
"This deployment has not been straightforward, with the initial phases significantly constrained by COVID-19 and the recovery to the UK heavily impacted by the withdrawal from Afghanistan," said Wing Commander Steve Lamping, Commanding Officer, 121 Expeditionary Air Wing.
"However, I am proud to say that the personnel of 121 Expeditionary Air Wing have stepped up and delivered, both in the air and on the ground.
"Working with the Romanian Air Force and wider regional allies we have proven our commitment to NATO and enhanced stability in the Black Sea region."
Cover image: RAF Typhoon (Picture: RAF).