Small bathrooms (under 40 square feet) need toilets that maximize floor space and clearance. The three strategies: (1) compact-elongated bowls (27-inch projection), (2) round-front bowls (26-inch projection), and (3) wall-hung toilets (entire tank concealed in wall, only the bowl projects).
For most small bathrooms, compact-elongated is the sweet spot — you get elongated comfort with 2 inches less projection than a standard elongated toilet. American Standard Edgemere Compact-Elongated ($329–$429), DeerValley DV-1F0026 Compact ($349–$419), Kohler Cimarron Compact ($349–$449) are the top picks.
For very tight bathrooms (under 30 square feet, powder rooms), round-front becomes necessary. American Standard Cadet 3 Round-Front ($229–$299), Glacier Bay All-in-One Round-Front ($199–$259), Niagara Liberty Round-Front ($259–$329) are the standard picks.
Wall-hung toilets are the premium small-bathroom solution. The bowl extends only 21–22 inches from the wall (vs. 27–31 inches for floor-mount), and the floor beneath is fully accessible for mopping. Cost is significantly higher due to the in-wall carrier requirement ($350–$900 for the carrier alone, plus $700–$1,500 plumber labor for the carrier rough-in). Total install runs $2,000–$3,500. TOTO MH Wall-Hung, Duravit Vero Air, Swiss Madison Avancer are the popular wall-hung picks.
Beyond toilet choice, consider whether the toilet should be repositioned in the bathroom layout — moving the toilet to a different wall position during a remodel can dramatically improve a small bathroom's usability, even though it requires plumbing work ($800–$2,000).