Subject: (Mention the purpose of writing the letter)
Dear Royson(Sir or Madam),
I am a member of the social group named________ (name of the group) and I am writing this letter on behalf of my group as we need some funds for the ________(mention the cause of the donation).
We will use money for _______ (mention where the money will be used). We will give you all the details of the accounts too. We would be thankful if you could contribute.
Thanks and Regards,