Travel listings in Rajasthan use "palace," "haveli" and "fort" almost interchangeably, but the three describe genuinely different kinds of buildings, built for different purposes — and the difference shapes what a stay actually feels like.
Palace
A palace was built as a royal or noble residence — a seat of family life and, often, local governance. Palaces typically include formal reception halls (durbar halls), separate wings for family and guests, and extensive gardens, since they needed to accommodate both daily domestic life and state occasions. Diggi Palace, built in the early 1730s as the residence of the Diggi royal family, follows this pattern — durbar hall, garden courtyards and family wings all still present in the building today.
Haveli
A haveli is a large traditional townhouse, historically built by wealthy merchant or noble families, centred on one or more internal courtyards (havelis often have multiple, arranged around business and family functions separately). Havelis tend to be more urban and compact than palaces, built into a city's existing street pattern rather than standing in open grounds.
Fort
A fort was built primarily for defence — thick outer walls, elevated positions, and a layout designed around military logistics rather than domestic comfort. Many Rajasthani forts incorporated palace quarters within their walls (Amber Fort is a well-known example), which is part of why the terms get blurred — a fort can contain a palace, but a palace on its own doesn't necessarily have fortification.
Why it matters for your stay
A fort hotel will generally have thicker walls, more dramatic elevated views, and a more military feel to its architecture. A haveli hotel will feel more urban and intimate, often in the middle of a city's old quarter. A palace hotel — like Diggi — tends to offer the most garden space, the most varied room typology (since rooms were built for different family members and purposes rather than uniformly), and often the strongest sense of ongoing family history, since palaces were built to be lived in rather than simply defended or transacted from.