The 2017–18 RFU Championship, known for sponsorship reasons as the Greene King IPA Championship, was the ninth season of the professionalised format of the RFU Championship, the second tier of the English rugby union league system run by the Rugby Football Union. It was contested by eleven English clubs and one from Jersey in the Channel Islands. The competition was sponsored by Greene King for a fifth successive season. The twelve teams in the RFU Championship also competed in the British and Irish Cup, along with clubs from Ireland and Wales.