My new boss is asking me to fill out a time-off sheet for any doctors' or dentists' appointments that I need to take during the day. (I've been here for 9 years and never had to before.) I am a salaried, exempt employee. From reading some of the other posts, it seems like he can do this.

My question: Must I use my vacation/sick/personal time, or can I tell them to account for it as overtime or comp time? I work on average 10-15 hours extra every week, including some weekend work (all of it in the office). I know it's not really "overtime," since I'm not an hourly employee, but I would hope that those extra hours could somehow be used to offset my doctors' appointments.

I agree with you, but they can take your PTO for not working core hours.

Agreed with Scott. Arguably it would be "fair" to allow a Salaried Exempt employee to make up time missed out of unpaid overtime, but this is not a legal requirement. There legally is no such thing as "comp time" for private sector employers. Employers can indeed legally reduce PTO/vacation balances for "core" hours not worked, even if these hours were made up with unpaid OT.

There is also legally no unpaid overtime.

I agree it's petty. But it's legal.