> For the complete documentation index, see [llms.txt](https://payments.govstack.global/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://payments.govstack.global/development-3/8-service-apis/8.5-business-to-government-b2g-payments.md).

# 8.5 Business to Government (B2G) payments

For Business to Government (B2G) transactions the following existing APIs would need to be used:

For Invoice Payments

* [billInquiryBiller](https://payments.govstack.global/development-3/8-service-apis/pages/oI4SYyoR2lszsNLkJwDT#id-8.3.1-billinquirybiller) - The existing API to retrieve invoice details detailed in the [P2G payments](/development-3/8-service-apis/8.3-person-to-government-apis-p2g-bill-payments.md) would be used to get bill details from the Bill Aggregator or Govt Entity.
* [markBillPayment](https://payments.govstack.global/development-3/8-service-apis/pages/oI4SYyoR2lszsNLkJwDT#id-8.3.3-markbillpayment) - The existing API to bill payment detailed in the [P2G payments](/development-3/8-service-apis/8.3-person-to-government-apis-p2g-bill-payments.md) would be used to mark the invoice as paid.

For RTP Payments

* [billerRtpReq](https://payments.govstack.global/development-3/8-service-apis/pages/oI4SYyoR2lszsNLkJwDT#id-8.3.4-billerrtpreq) - The existing API for to initiate a "Request to Pay" (RTP) as detailed in the [P2G Payments](/development-3/8-service-apis/8.3-person-to-government-apis-p2g-bill-payments.md) would be used try the Bill Aggregator or Govt Entity to initiate the RTP.
* [markBillPayment](https://payments.govstack.global/development-3/8-service-apis/pages/oI4SYyoR2lszsNLkJwDT#id-8.3.3-markbillpayment) - The existing API to bill payment detailed in the [P2G payments](/development-3/8-service-apis/8.3-person-to-government-apis-p2g-bill-payments.md) would be used to mark the invoice as paid.