How cold hardy is calamansi citrus?

Answer 1

Most labels I see is that it is cold hardy down to 18 deg F.
It is called Calamondin. It depends on the pattern of your winter. If your winter is too dicey, like suddenly cold and suddenly warm, then the cold hardiness is at 24 deg F. But if going into the winter is so gentle that allows time for calamondin to harden, then it could survive temperature down to 12 deg F.

Answer 2

Calimondin is considered cold hardy to 20 degrees but as stated, depends on the fluctuation of temps. I grow them in pots in zone 7 and keep them inside all winter. Get lots of fruits every year.