A checkbox showing a check mark inside the box. Not to be confused with the similarly named Ballot Box With Ballot emoji.
This emoji is not supported in Twitter names, possibly in an attempt to minimize confusion with a verified checkmark.
📅 Check Box with Check was approved as part of Unicode 1.1 in 1993
under the name “Ballot Box with Check”
and added to Emoji 1.0 in 2015.
Check Mark In Box