Lisa Sargent, a fundraising copywriter and author of the book Thankology, says it’s critical to treat supporters as close, valued partners in a thank-you letter. To that end, there are three little ...

If you’re at a friend’s house midweek and they say, ‘Would you like to stay for pasta?’ sending an effusive, florid thank you letter is a bit much. A warm text or email would do the trick.” ...

And yes, even if you don’t like the gift, you should still send a thank-you note—but there’s no need to mention that it wasn’t what you wanted or that you’ll be returning it, Goss says.