WooCommerce Purchase Order GatewayDeveloped by WooCommerce
Receive purchase orders via your WooCommerce-powered online store.
The Purchase Order Gateway extension for WooCommerce adds a field to the checkout screen where your customer enters in their purchase order number (provided by you directly to the customer in a manual agreement).
The Purchase Order Gateway requires no configuration to get up and running.
To tweak the instructions shown to the customer, visit the WooCommerce > Settings > Payments > Purchase Order screen.