Co-sleeping at a Japanese hotel is free for preschool children at all 6 chains whose official websites we checked, and the 5 chains that publish an elementary-school rule charge ¥0 to ¥2,000 (tax included) for elementary-school children (checked November 10, 2026; Super Hotel’s official FAQ only states that preschoolers stay free). Co-sleeping (添い寝, soine) means the child shares the adult’s bed instead of getting an extra bed or futon. The age limit for free co-sleeping is set by each chain’s or property’s own rules, so this article lists each chain’s official policy, explains the points that commonly cause confusion when booking, and highlights properties with many family-travel reviews.

How Much Does Co-Sleeping Cost, and Up to What Age Is It Free?

Here is the answer first. The official policies of the 6 chains we checked fall into 3 patterns:

• Free through elementary school: Toyoko Inn (東横イン), Comfort Hotel (コンフォートホテル) and Greens (グリーンズ) (Comfort Hotel explicitly states “up to 6th grade”)
• Preschoolers free, flat fee for elementary-school children: Route Inn Hotels (ルートインホテルズ) (elementary-school children ¥2,000, tax included)
• Preschoolers free / no extra charge for co-sleeping: Super Hotel (スーパーホテル), and Washington Hotel / Hotel Gracery (ワシントンホテル・ホテルグレイスリー)

Junior-high students and older are treated as adults under every policy. “Free” also applies only when the child sleeps in the same bed as an adult; if a child uses a bed alone, the adult rate applies — a rule shared by all chains.

Take Route Inn Hotels’ official FAQ as an example: preschoolers are free and elementary-school children cost ¥2,000 (tax included), and both apply when the guests exceed the room’s capacity. If one adult and one child use a room with a capacity of 2, the rate is for 2 adults, and co-sleeping must be booked through a dedicated plan. Some brands (Bizcourt Cabin / ビズコートキャビン) do not accept co-sleeping at all, so checking each hotel is the safest approach.

Co-Sleeping Policies by Chain (Checked on Official Websites)

The following reflects each chain’s official website and FAQ as checked on November 10, 2026. Chains are listed in Japanese syllabary order, which does not indicate ranking. Fees and conditions may vary by property and plan, so please confirm the latest information via the links before booking.

Compiled by the HotelBank Editorial Team from each chain’s official website (checked November 10, 2026; N=6 chains). Fees are per co-sleeping child per night. For Washington Hotel / Hotel Gracery, the table uses “no extra charge” to match the wording of the official FAQ. Toyoko Inn bed sizes differ at some hotels.

What this table shows is that there is no nationwide answer to “up to what age is co-sleeping free?” — the dividing line between chains is whether it is free only for preschoolers or through elementary school. At hotels and ryokan not listed here, even infants may fall into finely divided rate categories depending on whether meals and bedding are included. Rather than treating one chain’s fee as the going rate, the quickest route is to check the policy of the property you plan to stay at. Examples of chains that offer free co-sleeping for children up to 18 are also covered in Free Co-Sleeping Age at Japan Hotels: Up to 18 at Vessel, by Chain.

4 Points That Commonly Cause Confusion When Booking

1. Where to enter the number of children. On official websites, there are two methods: “do not count co-sleeping children; search by the number of adults only,” as at Toyoko Inn and Greens, and “enter the number of preschoolers to see rooms that allow co-sleeping,” as at Super Hotel. On OTAs, it is common to select the child’s age category (elementary school or infant, with or without meals and bedding) in a separate “Children” field, and the fee for the selected category is added to the total. If you book without entering a category, the hotel may need to confirm details on the day, so it is safest to always state the number of children, even when they co-sleep.

2. Whether there is a dedicated co-sleeping plan. Some chains, such as Route Inn Hotels, require co-sleeping to be booked through a dedicated plan. If you cannot find it among regular plans, look for plan names containing “添い寝” (co-sleeping) or “ファミリー” (family).

3. Children’s breakfast fees. Even when the stay is free, breakfast may be priced separately. Toyoko Inn offers free breakfast to co-sleeping children as well; at Greens, hotels with free breakfast also provide breakfast for co-sleeping children, while hotels with paid breakfast charge for the child’s portion. At hotels with paid breakfast, checking the child rate and whether same-day orders are accepted in advance avoids surprises at checkout. Details of Toyoko Inn’s free breakfast are covered in our Toyoko Inn brand guide.

4. Bed width and number of guests. As a general guide, singles are about 100cm wide, semi-doubles about 120cm, doubles about 140cm and queens about 160cm. For 1 adult and 1 preschooler, a semi-double or larger is recommended; for 2 adults and 1 child, a double or larger — or a twin with separate beds — makes for easier sleep. Toyoko Inn allows “up to 1 child per bed” for co-sleeping, so 2 adults staying in a twin can each co-sleep with 1 child per bed (available room types can be checked on each hotel’s official page). Towels and toothbrushes are generally provided for the room’s capacity, so ask the front desk if you need extras for children.

8 Properties With Many Family-Travel Reviews

Even if the co-sleeping terms fit, whether children will enjoy the stay is a separate question. From guest reviews aggregated by the HotelBank Editorial Team, the editors selected 8 properties from the top 100 by number of posts speaking positively about staying with children, and listed them in order of mentions (24 months from November 2024 to November 2026; properties with at least 10 mentions and at least 20 reviews. The top 100 accounted for 16,000 of 238,064 reviews).

Source: HotelBank Editorial Team research (aggregation of guest reviews; N=8 properties, 22,965 reviews in total, November 2024 – November 2026). Review excerpts are partial quotes translated from Japanese posts.

At resort-type properties, reviews highlight the ability to “spend the whole day inside the hotel,” with indoor play areas and buffets. Co-sleeping terms differ by property; for example, Grand Mercure Nasu Highlands Resort & Spa offers free accommodation and meals for co-sleeping children aged 0–6, but only for bookings made through its official website. Age categories and room capacities are summarized in a Japanese-language article on Grand Mercure Nasu Highlands’ child rates, co-sleeping ages and cheapest days.

If you are traveling with a baby and prioritize facilities, the Welcome Baby Inn certification system is also a useful guide for choosing where to stay.

Further Reading (in Japanese)

Frequently Asked Questions

Methodology and Sources

References and Sources

■ Data sources

Each chain’s official website and FAQ (6 chains, checked November 10, 2026) and guest reviews aggregated by the HotelBank Editorial Team (24 months, November 2024 – November 2026).

■ Assumptions

Fees are per co-sleeping child, per night, tax included, organized as stated in the official notices. Review-based properties are ranked by the number of posts speaking positively about staying with children; the editors selected 8 from the top 100 among properties with at least 10 mentions and at least 20 reviews. The order reflects mention counts and does not indicate which property is better.

■ Limitations

Co-sleeping conditions may change by property, plan and season; when booking, each chain’s latest official information takes precedence. Mention counts are an aggregation of review content and do not guarantee facilities or services. Bed widths are general guidelines; actual sizes vary by property.

■ Official websites (Japanese)

• Route Inn Hotels — FAQ
• Greens — FAQ
• Comfort Hotel — official website
• Super Hotel — FAQ
• Toyoko Inn — guide for guests with children
• Toyoko Inn — usage guide
• Washington Hotel — FAQ
• Hotel Gracery — FAQ