Upvote:3
The customs and passport control at Taipei Port is all in the same building in the port (which also houses the ticket office). We were there today, travelling with CSF.
You just turn up there (here's the plus code of the front door - 592R+55 Taipei, Taiwan), pick your tickets up if necessary and pass through security. A bus then shuttles you to the ferry door (like a bus taking you to the steps of an aeroplane from the terminal).
Took about 45mins to get from front door of office to stepping on the ferry so leave yourself some time.
Upvote:4
While not a definitive response, here are resources which may help. A 2014 article in the Taipei Times confirms that the Taipei-Pingtan route runs on Tuesday and Wednesday.
The Customs office at the port for the Keelung Port Border Affairs Team(Taipei Branch)is at No.123, Shanggang Rd., Bali Township, Taipei County 2F. Administration Building)02-86304169
The CSF ferry address is New Taipei City 24941 No. Bali Road commercial port area 123
CSF directions on how to get to Taipei Port:
The Taiwan Travel Service Center, Tourism Bureau in Taipei is open 08:00 ~ 19:00 daily, and is located at 1F-4F, No.240, Dunhua N. Rd., Songshan District, Taipei City 105 (Institute of Transportation Building).
Tourist Information Hotline : +886-2-2717-3737
24-Hour Toll-Free Travel Information Hotline : 0800-011765