Fair Pricing at Scale: Prorating Without the Headache

A customer upgrades from a $60 plan to a $180 plan on the 23rd of the month. Charging $180 immediately feels excessive. Waiting until next month gives away the upgraded service. Sending someone in finance to calculate the difference manually works, until the same thing happens 200 times.Proration solves a fairly ordinary problem: customers change subscriptions between billing dates. The calculation itself is rarely the hardest part. Trouble starts when companies have inconsistent rules for upgra