I'm skeptical December 2025 BookTok will suddenly birth brand-new trends. The real influence comes from trends born earlier in the year, like a dark academia revival or a specific romance subgenre, finally hitting their peak saturation right when everyone's making holiday TBRs. Last year, 'The Inheritance Games' style locked-room mysteries dominated December because the trend started in September and everyone wanted cozy, puzzle-like reads. So watch the fall trends, not December itself.
Platforms will absolutely push 'holiday romances' and 'wintry fantasies'—think books with snowy covers—but the genuine picks will be whatever BookTok has been analyzing for months. If cozy fantasy ('Legends & Lattes' vibes) stays big, that'll be the go-to for holiday hygge. If dark romance peaked in October, it'll still be on lists but framed as a 'spicy escape from family drama'.
Ultimately, the algorithm matches mood with season, but the books were already trending. My own list? Probably whatever fantasy series people were dissecting for lore back in October.