I’d say something like it has been such a pleasure working with you that I feel the need to give back to the less fortunate. X charity seems to me to be the most effiecent way to do that as far as I know and I couldn’t have supported it without you.
One idea to be less preachy is to frame your donation as a thank you from its recipients to your client. E.g. you could say something like: “I got the money you wired me. Thank you. I thought it might warm your heart to know that I donated 10% of the money to X organization, and as a result Y outcome occurred. So, you have made some Z individuals quite thankful as well!” Basically sort of give them a taste of what it feels like to give effectively.
BTW, I suspect communicating this info will work better in live conversation. If you communicate in live conversation, you create a space for them to ask questions and learn more, plus over time you might get better at bringing it up in a way that’s not weird.
One idea to be less preachy is to frame your donation as a thank you from its recipients to your client. E.g. you could say something like: “I got the money you wired me. Thank you. I thought it might warm your heart to know that I donated 10% of the money to X organization, and as a result Y outcome occurred. So, you have made some Z individuals quite thankful as well!” Basically sort of give them a taste of what it feels like to give effectively.
BTW, I suspect communicating this info will work better in live conversation. If you communicate in live conversation, you create a space for them to ask questions and learn more, plus over time you might get better at bringing it up in a way that’s not weird.