Japan has 160+ highway bus operators. These 5 cover ~70% of market share and nearly every major route.
Willer Express
Largest operator. Famous Cocoon and Luxia seats with personal canopy. Strong routes: Tokyo↔Osaka, Tokyo↔Kyoto, Kawaguchiko. Willer Pass 3-day ¥12,000.
JR Bus (Kantō / Tōhoku / Tōkai)
Reliable, punctual, standard 3/4-across seats. Tokyo↔Sendai, Tokyo↔Osaka, Tokyo↔Nagoya. JR Pass doesn't apply.
VIP Liner
Premium Gran Class with 170° flat-bed seats. ¥10,000–¥15,000. Routes: Tokyo↔Osaka, Kyoto, Fukuoka.
Keio Bus
Strong on Shinjuku → Kawaguchiko, Matsumoto, Nagano. ¥2,000–¥4,000. Popular with tourists.
Kousoku Bus
Aggregator — often the cheapest. Quality varies by sub-operator; check reviews.
