Hi, there is no direct bus from Hangzhou airport to Ningbo. You can take a taxi to Xiaoshan Bus Station and then take long-distance bus to Ningbo.
There is direct bus from Hongqiao Airport to Ningbo. The last bus depart at about 20：30.

Last train from Hangzhou -> ningbo at 2103hrs
Last bus from hangzhou -> ningbo around 2100hrs

Last train from Shanghai -> Ningbo at 1935hrs
Last bus from Shanghai -> ningbo around 2030hrs

Train or bus, its hard to suggest at this time but it completely depend upon your location in starting city.

As someone already wrote no bus from ahngzhou airport to ningbo but there is bus from shanghai. If you are landing at shanghai from an international flight than i suggest you to make your route via hongkong, hongkong-ningbo has direct flights.