Abstract: The various embodiments herein each include at least one of systems, methods, and software for single and multi-tenant rule driven crediting systems and methods, such as may be utilized for implementing reward programs that reward customer loyalty. One such embodiment in the form of a method includes receiving input defining a rule to be applied against transaction data, the rule identifying at least one applicable transaction type and a value to be credited to an account associated with an account involved in the transaction. The method further includes storing the rule in a rulebase of a plurality of rules. The method also may include executing a rules engine to apply rules of the rulebase against transactions in a transaction system where a type of a respective transaction matches the at least one applicable transaction type of a respective rule.