Start building with the BILL API

Integrate with the easy-to-use BILL API and leverage our trusted B2B payments platform to send and receive payments for your business.

❗️Changes to BILL API access

At this time, we are providing BILL API access only for select partners. Please reach out to your account manager for more information.

curl --request POST \
     --url \
     --header 'Accept: application/json' \
     --header 'Content-Type: application/x-www-form-urlencoded' \
     --data devKey={developer_key}
     --data sessionId={session_id}
     --data 'data={

Building blocks for developers

Create custom branded experiences with end-to-end Accounts Payable (AP) and Accounts Receivable (AR) workflows at scale.

Safely build and test with API calls in our Sandbox environment to confirm your expectations.

API reference

View sample code in your choice of language and test sandbox API calls in the documentation.

Jump to the API reference →


Step-by-step walkthroughs for use cases like paying a vendor and sending a customer invoice.

See recipes →

More resources

Learn about all the educational resources available at different stages of your app development.

Using this website →

Why integrate with BILL?

Leading payments platform

Use the BILL API to process high volumes of payments simultaneously. Leverage our automatic syncs and remove manual data entries with QuickBooks, Intacct, NetSuite, Dynamics, Xero and other integrations.

Faster & more efficient payments

We facilitate your AP process with faster electronic payments or standard checks. Your AR customers receive and pay invoices digitally. You pay or get paid in half the time as compared to paper-based processes.

Designed with your security in mind

We manage over $70B annually and take financial security seriously. All data in transit is encrypted using industry standard Transport Layer Security (TLS).