Jimin and Taehyung donating their shirts and signatures for an auction at '2017 WeAJa Charity Flea Market.' http://www.kstarlive.com/BTS-Jimin-and-Taehyung-to-Participate-in-a-Charity-Event--Donating-to-the-Needy-5891331
As he promised to Armys in 2014 that he'd buy beef if he becomes successful. 4 years later(on his 25th birthday), he donated beef to 39 orphanages in the name of ARMY

Not to forget the "Love Myself" Campaign in collaboration with UNICEF! 3% of the Love Yourself album sales have gone directly to BTS' Love Myself fund!
And I'm sure there are so many other donations that they made and we don't know about them. As BTS never disclose their donations themselves. We always get to know to about them through the recipients.
Incase I missed something, feel free to add!
While you're here, donate here if you can! #2MforBLM https://btsarmyxblm.carrd.co/#
Incase you wanna help the BLM movement but you're broke like me:
https://twitter.com/cooIpeopIe/status/1267937798755102723?s=19
https://twitter.com/cooIpeopIe/status/1267937798755102723?s=19
Also, if you're an ot7, queer friendly and support BLM movement, LET'S BE MOOTS! I'LL FOLLOW BACK EVERYONE!