Proration

What is proration?

Proration is a billing adjustment that occurs when a customer changes their subscription plan mid-cycle. Instead of charging the full price of the new plan from the next billing date, proration calculates a partial charge or credit based on the time remaining in the current billing period.

How proration works

If a customer upgrades from a $50/month plan to a $100/month plan halfway through their billing cycle, proration charges them $25 for the remaining half-month at the higher rate while crediting them for the unused portion of their current plan. This ensures the customer pays fairly for what they actually use.

Proration calculations are handled automatically by most billing systems (Stripe, Chargebee, etc.) but the business must decide on the proration policy: charge immediately, charge at next invoice, or offer credit.

Why proration matters for payment health

Prorated charges can cause unexpected payment failures if the resulting invoice amount differs significantly from the customer's usual charge. A customer accustomed to a $50 monthly charge may have their card flagged by the issuer when a $75 prorated charge appears. Clear communication about billing changes and consistent charge patterns help minimize unnecessary declines.

Proration also affects MRR calculations. Prorated upgrades and downgrades must be properly accounted for to maintain accurate revenue reporting.