Is mortgage interest on an RV or mobile home tax deductible?
Yes. You're allowed to deduct the interest on a loan secured by your main home (where you ordinarily live most of the time) and a second home.
A mobile home, RV, house trailer, or houseboat that has sleeping, cooking, and toilet facilities counts as a main or second home, and as long as it meets all the other requirements for deducting mortgage interest, you can claim the interest like an immovable home.
You can enter these deductions under Federal Taxes > Deductions & Credits > Mortgage Interest, Refinancing, and Insurance (Form 1098). Even if you don’t have a 1098, you’ll still need to enter the requested information from an alternate source, such as your mortgage lender or year-end mortgage statement. In that case, just enter everything when prompted as though you have a 1098. (Because you’ll be entering the equivalent of the amounts from the different numbered boxes of the 1098 without actually having that form).
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