Japan Trials First Full-Flat Sleeper Bus

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Japan's first trial run of a highway bus with full-flat seats is now underway, aiming to challenge the common view of night buses as cramped and tiring.

The seats were jointly developed by Kochi-based operator Kochi Ekimae Kanko, a local model-making company, and a machinery manufacturer. Made entirely in Kochi, they meet the full-flat seating guidelines introduced by the Ministry of Land, Infrastructure, Transport and Tourism in November 2024.

Since March, Kochi Ekimae Kanko has been operating a weekly round trip between Tokyo and Kochi on a trial basis, receiving positive feedback. With hotel prices climbing due to increasing inbound tourism, the service also aims to appeal to cost-conscious travelers.

Deep Sleep?

The full-flat seats are called Sommeil Profond, French for "deep sleep." Two rows of seats, front and back, convert into bunk-style beds, creating a private space similar to a capsule hotel. A large coach was remodeled to accommodate 24 seats across 12 bunk-style units arranged in three rows. The trial service began on March 11, running once a week between Tokyo and Kochi or Tokushima.

The longest stretch of the trip takes about 13.5 hours one way. Passengers can stay fully reclined the entire time. Each seat is enclosed by curtains for privacy and comes with amenities like a blanket and pillow, offering a semi-private experience. The regular fare is expected to be around ¥13,000 JPY (about $90 USD), though the trial price has been set between ¥7,000 and ¥7,500.

Customer Reviews

On the morning of May 21, the trial bus arrived at Kochi Station fully booked with passengers traveling for sightseeing or business.

Yukari Ikezawa, a 37-year-old office worker from Kochi who took the round trip, said, "The vibrations bothered me a little, but on the way back, I was so tired I slept soundly. I felt much less fatigued compared to a regular bus."

A company representative added, "These seats significantly reduce fatigue compared to standard ones. And since passengers can sleep while traveling, it also helps cut down on hotel expenses."

*Seats arranged to make full-flat "beds." (Courtesy of Kochi Ekimae Kanko)*

Chinese Sleeper Buses

About 30 years ago, Kochi Ekimae Kanko's Chairman Kuninori Umehara saw sleeper buses during a visit to China. The company considered bringing the concept to Japan but had to put the idea on hold due to the lack of a legal framework at the time.

Around 10 years ago, the company confirmed that there were no regulations on seat reclining angles. This opened the door to the idea of converting traditional seat designs into fully flat beds, and development began.

Creating bus seats involves specialized knowledge and technical skills. To take on the challenge, the company partnered with local model maker Thermal Kobo and industrial machinery manufacturer Kakiuchi. Together, they repeatedly refined prototypes that could fold flat, maximize cabin space, and meet safety standards.

They also consulted closely with Japan's transport ministry. It was determined that as long as the seats could return to an upright position, the bus would pass inspection under the Road Transport Vehicle Act.

Sleeper Guidelines

At the time, international safety standards for vehicle seating were based on a 25-degree seatback angle, and there was no established method to assess the safety of fully flat seats. However, as global discussions around safe seating in various postures began to grow, the ministry anticipated rising demand and introduced formal guidelines in November 2024.

The guidelines require the following:
A fall-prevention plate that can withstand 900 kilograms of force
Two-point seatbelts
Padding and safety features to prevent falls from the head and sides
Clear evacuation routes and secure luggage storage

Kochi Ekimae Kanko refined its design to meet these standards and successfully turned the concept into reality.

Seat Count vs Comfort

Since the trial began, buses equipped with Sommeil Profond seats have been nearly full. Surveys show that about 80% of users gave the ride high marks, especially for reduced fatigue and improved sleep quality.

The most common complaint, however, was the narrow bed size. In bed mode, each seat measures 180 cm (5.9 ft) in length, 48 cm in width, and 51 to 73 cm in height, depending on the seat. Some larger passengers reportedly have to curl up to fit.

"There's definitely room for improvement," said a company representative. "But seat size is closely tied to pricing, so we have to be careful when considering any changes to the design."

Wider seats would improve comfort but reduce the total number of seats. Since operating costs per bus trip — such as fuel — are mostly fixed, fewer seats would lead to higher fares. For reference, a standard 28-seat, three-row bus charges about ¥10,000 on the Kochi–Tokyo route. The full-flat model accommodates 24 seats, allowing fares in the ¥13,000–¥14,000 range.

Inbound Tourism

Passengers have also requested more storage space and power outlets. The company is reviewing these suggestions and plans to expand service this fall with two buses offering four round trips per week.

Looking ahead, Kochi Ekimae Kanko aims to market the Sommeil Profond model nationwide. Talks are already underway with bus operators in Tohoku and Kyushu, and interest has been strong.

A representative said, "Eventually, we believe half of all overnight highway buses could adopt full-flat seating. By switching between upright and flat modes, these buses could even serve as a new option for inbound tourism. We want to keep improving and expand this model across Japan."