The role of NFBs is to supplement the mass carriers. The supplementary role of NFBs include:

(a) relieving heavy demand on the franchised bus and green minibus services primarily during the peak hours; and
(b) filling gaps of passenger demand which cannot be met viably by the regular public transport services.

Based on the above criteria, NFBs are to provide tailor-made service to specific groups of passengers. As at 31 May 2015, there were 7,046 registered non-franchised public buses in the territory.
  

For public transport route search:
Hong Kong eTransport

 
No. of Registered Non-franchised Public Bus PDF (25KB)
 
Non-franchised Private Buses
As at 31.5.2015, there are 601 registered private buses. No. of private buses with different service endorsements is appended below:
Service endorsement No. of private buses
B01 - Student Service 78
B02 – Employees’ Service 231
B03 – Disabled Persons’ Service 252
B04 – Others Service 253
Note : As non-franchised bus can be granted with more than one service endorsement, the total number of service endorsement does not equal to the total number of non-franchised bus.