Abstract: Generally described, the present invention relates to a recurring billing/ordering application that works with an ecommerce platform to enable a merchant to sell products on a recurring basis. The recurrence application enables the merchant to create subscriptions for recurrence frequency sets and assigned products, creates recurrence rule/option sets corresponding to the frequency sets for the assigned products, collects from the ecommerce platform its assigned rule-set IDs for the frequency set, and saves the IDs and the corresponding frequency set in a database. Then upon receiving a customer order for a product with a recurrence frequency selected from a frequency set, the recurrence application collects rule-set IDs from the ecommerce platform, checks the database for any of those IDs, and upon finding a match uses the corresponding frequency for processing the recurring orders, without having to be redirected from the ecommerce platform to an external account to obtain this information.