Below is a table of WooCommerce payment gateways which have been tested with WooCommerce POS.
For the best experience we recommend the free Stripe gateway, this is the only gateway officially supported by both WooCommerce and WooCommerce POS.
WooCommerce Stripe Payment Gateway by WooCommerce
WooCommerce Authorize.Net AIM Gateway by SkyVerge
WooCommerce PayPal Powered by Braintree Payment Gateway by WooCommerce