Selena Gomez and Benny Blanco are head over heels and living large -- because TMZ has learned they dropped millions on a dreamy Beverly Hills mansion.

Multiple real estate sources tell TMZ ... Selena and Benny went all-in on a Spanish-style pad with 7 bedrooms and 12 bathrooms in December -- for a jaw-dropping $35 million!

The resort-like grounds come with multiple structures, including a library and a grand swirling staircase. Outside there's a glass greenhouse solarium, a fitness center, and a pool.

The crib has celebrity history ... a couple years before Selena and Benny purchased the place, it was owned by a big-time Hollywood director.

SG and BB's purchase at the end of last year made it one of Beverly Hills' priciest deals of 2024.

The Rare Beauty founder is a billionaire, so this splurge probably feels like pocket change to her.

The mansion could've played the role as the backdrop for the duo’s Valentine’s Day shenanigans, with Benny going all out and gifting Selena ... a bathtub filled with cheese!