定てい額がく制せい

noun

flat-rate system; fixed-rate billing

Refers to a billing or pricing model where a fixed amount is charged regardless of usage, common for subscriptions, utilities, or services.

• このサービスは定てい額がく制せいで、毎まい月つき同おなじ料りょう金きんです。

  This service is a flat-rate system, so the fee is the same every month.

• 定てい額がく制せいのプランに切きり替かえると、使つかい放ほう題だいになります。

  If you switch to a flat-rate plan, you can use it as much as you want.