How do I check my handling time on eBay?

The handling time is stated on the Shipping/Payments screen, right next to the sales tax and above the return policy. When the seller has an extended handling time (more than 3 days), it is also stated on the Description screen, upper right corner.

What is the default handling time on eBay?

In September 2019, eBay will update the pre-filled value in the Handling time field in the eBay listing flows to 1 day. Currently, eBay listing flows are pre-filled with 2 or 3 days. The 1 day handling time change will be an optional default when you create new listings.