I have set up 'pay bills online'. What are the fees for paying vendors/contractors via pay bills online?

Thanks for posting a question here in the Community, @vincenzo.

The fees or pricing for the online bill pay depends on the type of plan you have. Please check out this article to learn more about the fees per plan type: What are the fees per plan type for the Online bill pay subscription?

I'm also thinking of adding these handy articles that you can read through to learn more about Online bill pay in QuickBooks Online:

• Online Bill Pay Overview.
• How to Pay bills using Online Bill Pay.

Fill me in if you have more questions by leaving a comment below. I'm around in the Community to help you achieve your goals. Take care and have a nice day!

@vincenzo 

If you wish to stretch your cash flow by creating up to a 45-day float by paying bills via a credit card, even if the vendor doesn’t accept credit cards, you will need additional option.