Also known as base premium.
A cedant’s premiums (written or earned) to which the reinsurance premium rate is applied to calculate the reinsurance premium.
Often, Subject Premium is gross/net written premium income (GNWPI) or gross/net earned premium income (GNEPI), where the term “gross/net” means gross before deducting reinsurance premiums for the reinsurance agreement under consideration; but net after all other adjustments, e.g., cancellations, refunds, or other reinsurance.
Normally, Subject Premium refers to premium on subject business.