Every internet service provider has to decide how subscribers pay: before they use the internet, or after. Prepaid billing protects your cash flow; postpaid billing is what many offices and long-standing customers expect. This guide compares prepaid and postpaid broadband billing for ISPs in India, shows when each model works best, and explains how to run both without losing track of dues.
What is prepaid broadband billing?
In prepaid billing, the subscriber pays for a plan before using it, usually for 1, 3, 6 or 12 months. The plan has a start date and an expiry date. When it expires, the subscriber recharges again. If they do not, the connection stops.
Most home broadband in India, especially from local operators and FTTH ISPs, now runs on prepaid recharges.
What is postpaid broadband billing?
In postpaid billing, the subscriber uses the internet first and pays a bill at the end of the billing cycle, usually monthly. The ISP raises an invoice with a due date, and the subscriber pays within that period.
Postpaid is common for business connections, offices, leased lines and older customers who have always paid this way.
Prepaid vs postpaid: side-by-side
| Prepaid | Postpaid | |
|---|---|---|
| When the subscriber pays | Before using the plan | After the billing cycle |
| Cash flow for the ISP | Money comes in upfront | Money comes in 30 days or more later |
| Risk of unpaid dues | Very low | Higher; dues can build up for months |
| What happens on non-payment | Plan expires and the connection stops | Bill goes overdue; you follow up, then suspend |
| Collection effort | Reminders before expiry | Reminders, follow-up calls, visits |
| Preferred by | Home users, students, rented homes | Offices, businesses, long-term customers |
| Long plans and discounts | Easy to sell 3, 6 and 12-month plans | Usually month to month |
| Invoice | GST invoice at each recharge | GST invoice at each billing cycle |
When prepaid billing suits your ISP
- Most of your subscribers are home users. They are used to recharging mobile plans, and broadband feels the same.
- Dues are your biggest problem. With prepaid, nobody uses the internet without paying first.
- You have many subscribers and a small team. Prepaid needs reminders, not collection visits.
- Your area has rented homes or high churn. Subscribers who move away do not leave unpaid bills behind.
- You want to sell longer plans. 6 and 12-month plans with a small discount bring cash in early and reduce churn.
When postpaid billing suits your ISP
- You serve offices and businesses. They pay against a monthly GST invoice and often need it for their accounts.
- You sell high-value connections such as dedicated or leased lines, where a business will not accept a sudden cut-off.
- You have long-standing, reliable customers who have paid on time for years.
- Your competitors in the area offer postpaid and switching everyone to prepaid would push customers away.
The practical answer: run both, with clear rules
Most ISPs end up with a mix: prepaid for home subscribers and postpaid for businesses. That works well if each model has clear rules.
Rules for prepaid subscribers
- Send reminders before expiry, with a payment link.
- Stop the connection automatically on the expiry date, the same way for everyone.
- Restore it the moment the subscriber recharges.
Rules for postpaid subscribers
- Raise the GST invoice on a fixed date every month.
- Set a clear due date and a credit limit, for example one month’s bill.
- Remind before the due date, follow up after it, and suspend if the bill stays unpaid beyond your limit.
- For new or small postpaid customers, consider a security deposit.
For more ways to keep collections on track, see how ISPs can collect broadband dues on time.
How to move subscribers from postpaid to prepaid
If postpaid dues are hurting your business, you can move home subscribers to prepaid in stages:
- Start with new connections. Every new home subscriber joins on prepaid.
- Clear old dues first. Ask existing postpaid subscribers to settle their balance before switching.
- Give a reason to switch. A small discount on 3, 6 or 12-month prepaid plans makes the change feel like a benefit.
- Explain the new rule clearly. Tell subscribers the expiry date and that the connection renews as soon as they pay online.
- Keep businesses on postpaid if they need monthly invoices for their accounts.
GST is the same in both models
Whether a subscriber pays before or after, broadband is a taxable service and needs a proper GST invoice. In prepaid billing the invoice is raised at each recharge; in postpaid billing it is raised at the end of each cycle. Read more about GST billing for ISPs in India.
How ISPMate handles prepaid and postpaid billing
ISPMate is cloud-based ISP billing software for internet service providers in India. It supports both models in one system:
- Prepaid recharges and postpaid monthly cycles, with a GST invoice created automatically for each
- Renewal and due-date reminders by SMS, and WhatsApp through ISPMate’s QuickMessage platform
- Online payments by UPI, card or net banking, recorded against the subscriber automatically
- Automatic suspension on expiry and instant reconnection on payment through RADIUS
- A customer portal and app where subscribers see their plan, expiry, dues and payment history
- Reports on collection, pending dues and plans expiring soon
Frequently asked questions
Which is better for an ISP, prepaid or postpaid billing?
For most home broadband subscribers, prepaid is better because the ISP is paid before the service is used and unpaid dues almost disappear. Postpaid suits offices and business connections that need monthly invoices. Many ISPs use both.
Can an ISP offer prepaid and postpaid plans at the same time?
Yes. Most ISPs run prepaid for home users and postpaid for businesses. Billing software that supports both models keeps the invoices, reminders and suspensions separate for each.
How do ISPs stop postpaid dues from building up?
Raise invoices on a fixed date, set a clear due date and credit limit, send reminders before the due date, follow up after it, and suspend the connection if the bill stays unpaid beyond the limit.
Is GST charged on prepaid broadband recharges?
Yes. GST applies to broadband service whether it is prepaid or postpaid. In prepaid billing, a GST invoice is raised at each recharge.
How can I move my subscribers from postpaid to prepaid?
Start with new connections on prepaid, clear old dues before switching existing subscribers, offer a small discount on longer prepaid plans, and explain the expiry and renewal rules clearly.
Want to run prepaid and postpaid billing from one system? Book a free ISPMate demo or call +91-9310313545.