Postpaid and Landline Bill Payment API: A Practical Guide

October 25, 2026 2 min read By A1Topup Team Utility API

Key takeaways

Postpaid is a bill, not a recharge: fetch first
Landlines often need the STD code and account number
Keep the reference number for every payment

Postpaid customers are some of the most loyal at any counter: the bill comes every month, the amount is fixed, and they want it done in a minute. The API side is simple once you know the one or two extra fields each operator wants.

Postpaid mobile

Select the operator and enter the mobile number.
Fetch the bill: name, due amount, due date.
Confirm with the customer and pay.
Print or share the reference number.

Landline extra fields

Operator	number	Extra field
Airtel Landline	Landline number	STD code
BSNL Landline	Landline number	STD code + account number
MTNL Delhi	Landline number	CA number

The full list of parameters is in the API documentation.

Pro tip

Save the STD code with the customer’s number the first time. Next month the payment takes ten seconds.

Common mistakes

Sending the landline number with the STD code joined in
Paying a typed amount instead of the fetched one
Not keeping the reference for disputes

Conclusion

Add postpaid and landline next to electricity and gas bills, and your counter covers almost every monthly bill a family pays.

Add bill payments

Postpaid, landline and utility bills on one API.

Utility bill payment API API documentation

Frequently asked questions

Is postpaid bill payment different from prepaid recharge?

Yes. Postpaid is a bill payment: you fetch the due amount first and then pay it.

What extra fields do landline bills need?

Usually the STD code, and for some operators the account number.

Can partial payments be made?

It depends on the biller; always show the fetched due amount to the customer first.

Have a question? Talk to our team

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