I would say for the most part, when people use the word "intimate" they are referring to being romantic, or maybe things they only ask their significant other or someone they are close to. but a personal question is just something you might not everyone to know, for example if someone you didn't like asked "do you have a boyfriend?" the response might be "that question is a bit personal."

Intimate questions are more personal than personal questions. Intimate questions might only be expected to be asked by your mother or your doctor or nurse or your boyfriend or husband. Personal questions might be asked by your employer, or your bank, or maybe your landlord, but they should only be asking questions that they have a reason for wanting to know-- like what is your address, what is your phone number, if you have large outstanding debts, if you have ever been convicted of a crime or been in prison, if you are using drugs. They just want to know how stable of a person you are to get some idea of whether they can trust you. A man that is interested in you might ask some personal questions like if you are married, what do you do, what kinds of things that you like to do, what food you like, what music you like. He had better not ask intimate questions unless you allow him to enter your private life to a large degree. These are all personal questions, and you have every right not to answer because if you do not intend to have a future with him then they are none of his business to know. None of them are intimate questions, though.

Hmm. When I think of "personal questions" I think of questions that relate to their background. If I think "intimate questions," it sounds more like questions you would ask your partner or someone you have an intensely strong relationship to.

A personal question can be anything that isn't strictly business. If you don't know someone well, and you want to ask them something that you aren't sure would insult them or not (because you are not a good friend), it's polite to ask, "Do you mind if I ask you a personal question?" It can be something as innocent as "I noticed that you have an accent. Where are you from?" An intimate question is always something of a deeply personal, and most likely sexual, nature. It goes FAR beyond just personal.