Gatum supports two billing models for clients: prepayment and postpaid. You choose which model works best for each client based on your business relationship with them.
With prepayment, a client can only send traffic when their balance is positive. If the balance runs out mid-campaign, messages sent from the web panel go to the Waiting SMS queue. Messages sent via SMPP or API are dropped.
This model works well for new clients – they pay upfront, and you have no risk of unpaid debt.
With postpaid, you set a credit limit for the client. They can send traffic beyond their balance, up to the credit amount you've defined. On top of that, you can add a temporary overdraw for situations where the client urgently needs to send more than their credit allows.
This model suits clients who can't always predict their monthly spend in advance – they send traffic throughout the period and pay the total at the end.
To set up credit and overdraw limits for a client, see How to Top Up the Balance for a Client.
