Rt Hon.

The Right Honourable (The Rt Hon. or Rt Hon.) is an honorific style traditionally applied to certain persons and to certain collective bodies in the United Kingdom, Canada, Australia, New Zealand, India, some other Commonwealth realms, the Anglophone Caribbean, Mauritius and occasionally elsewhere. "" in this context is an adverb meaning "to a great extent or degree". It is used only for living people.

"The Right Honourable" is added as a prefix to the name of various collective entities such as:

See also the collective use of "Most Honourable", as in "The Lords of Her Majesty's Most Honourable Privy Council" (the Privy Council).

The honorific is normally used only on the front of envelopes or other written documents.

In the House of Commons, Members of Parliament refer to members not as "the honourable member for ... (constituency)" but as "the right honourable member for ..." if they are Privy Councillors but now hold no ministry. To save having to recall constituency names in direct replies, the use of "the honourable lady/gentleman/member" or "the Minister (often, for department)/Chancellor/Prime Minister" is available to refer to members not in their own party (or coalition) where the person referred to has already spoken. Similarly, those in their own party are referred to as "my honourable friend" or, for Privy Councillors, "my right honourable friend". Other honorifics used in addition for those members in relevant professions (for example, "honourable and reverend", "honourable and gallant" and "honourable and learned") are now rare in the Commons.

Generally within the Commonwealth, ministers and judges are The Honourable unless they are appointed to the Privy Council of the United Kingdom, in which case they are The Right Honourable. Such persons generally include Prime Ministers and judges of the Court of Appeal of New Zealand, and several other Commonwealth prime ministers. Provided they are Commonwealth citizens, foreign judges appointed to the Judicial Committee of the Privy Council are entitled to the honorific as well, although the appellation may be ignored in the judge's home country.

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