The UCSA runs a private online group with 33.1k members (as of February 2022), and clubs are welcome to post there.
The group’s membership is a mix of current students and members of the wider community, who use it to chat and list items. All current students are welcome to join.
Your club might find this a good place to advertise your upcoming events and special messages. It’s easy to do – just sign up to the group as an individual or via your club Facebook page.