A Registered Psychotherapist is a Canadian credential, principally used in Ontario, where psychotherapy is regulated by law as a distinct health profession, unlike in the UK where the title psychotherapist itself carries no legal protection.
A statutory, rather than voluntary, standard
RPs are registered with the College of Registered Psychotherapists of Ontario, hold a recognised qualification, and work within a legally defined scope of practice, backed by statutory complaints and disciplinary procedures should something go wrong. This gives clients in Ontario a stronger formal safeguard than exists for the equivalent title in the UK.
How this compares to the UK
In the UK, by contrast, psychotherapist is not a protected title, and registration with a body such as UKCP or BACP remains voluntary rather than a legal requirement to use the title. This difference is genuinely worth knowing if you are comparing practitioners or considering treatment across the two countries, since the underlying level of formal accountability differs considerably between them.