Well-to-do means having enough money to live comfortably, with some extra for nice things beyond basic necessities. A well-to-do family can afford a pleasant home, occasional vacations, and the things they need without constant worry about money. They're not necessarily wealthy enough to own mansions or private jets, but they're financially secure and comfortable.

The term sits between “getting by” and “rich.” A well-to-do dentist might drive a nice car and send her kids to good schools, while a truly wealthy person might own multiple houses and never look at price tags.

You might describe a neighborhood as well-to-do if the homes are well-maintained and the residents seem financially comfortable. The phrase has an old-fashioned, almost genteel quality to it. People don't usually call themselves well-to-do: it's a polite way others might describe someone who's clearly doing fine financially without being very showy about their money.