How can we go from Taichung to Taoyuan International Airport? How long will it takes?

There are three bus companies between Taichung and TTIA: Kuo-Kuang, Freego and Ubus. Cost of a ticket NT$ 240. Driving time 2:10.
Frequency once or twice an hour, that depends on the bus company and your own departure times.

Of course you can take the Taiwan High Speed Rail between Taichung and Taoyuan in about 40 minutes at NT$ 590, but on both ends you'd have to take a free transfer bus at about 30 minutes each.

So a regular highway bus may be more comfortable and efficient with bags.

See 'transport' on the official website of Taoyuan airport.

Thank you for your quick reply. Very much appreciated.

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