The 19-year-old boundary Under current regulations, young men can freely travel back and forth to mainland China without restriction up to December 31 of the year in which they turn 18. However, from January 1 of the following year they will face different rules depending upon whether the enterprise in which their parent or parents work has received approval to invest in the mainland.
19 歲的分界點依照規定，18 歲之前，以及滿 18 歲開始到當年的 12 月 31 日之前，役男要赴大陸觀光或就學，沒有任何管制，可以自由出入；一旦滿 18 歲，從次年的 1 月 1 日起，依父母任職企業的核准與否，就會有不同的待遇。