Most textile recyclers do no welcome any kind of undergarment.
Note that Project Uplift Singapore, which used to collect bras for beneficiaries in developing countries, ceased operations in 2020.
Bra put in these bins are passed on to those who need them. Wash first.
Help a sister out!
You can giveaway or sell bras through apps and freecycling channels.
Don't be shy! Lots of people are sharing their old bras this way.
Unfortunately most charities and textile recyclers will not take these. If it is no longer suitable for reuse, bin it.