Twilio's paid support plans are billed on a per-month basis according to your product usage. Customers are free to upgrade or downgrade their service plan at will, but mid-month plan changes will be pro-rated. This guide explains how support plan changes are calculated.

Pro-rating explained

For both usage and flat based support, customers will get charged for support on a pro-rata basis from start date of their support plan.

For example, here's what you can expect if you upgrade your service plan on the 15th of the month:

• Your upgraded support plan benefits will become immediately available on the 15th.
• You will be charged at the beginning of the next month based on the following pro-rating calculations:
  Total monthly support charge * (Days support plan was active / Days in month)

Notice: Usage for all projects and subaccounts that share the same support plan will count towards calculating your total support charge.