Peach vs. Jetstar Japan vs. Skymark Carry-on Baggage Rules Compared: What Differs in Weight and Size
The carry-on baggage rules of Japan's three domestic LCCs (Peach Aviation, Jetstar Japan, and Skymark) have similar size limits, but the weight limits and the way item counts are calculated differ. Peach and Jetstar Japan are the strictest, capping the combined weight of personal items and carry-on baggage at 7kg, while Skymark allows up to 10kg. For size, Peach and Skymark use a single standard of 115cm total for three dimensions combined (each side within 55 x 40 x 25cm), whereas Jetstar Japan splits the allowance into under-seat items (40 x 30 x 20cm) and overhead-bin items (56 x 36 x 23cm), with an even smaller limit of 48 x 34 x 23cm on Q300 aircraft. Starting April 1, 2026, a new shared rule from the Regular Airlines Association (定期航空協会) also added a condition: passengers may only bring bags that they themselves can lift and stow in the overhead bin, in terms of both size and weight.
The Three Airlines' Rules at a Glance
| Item | Peach Aviation | Jetstar Japan (rules as of August 2026) | Skymark |
|---|---|---|---|
| Number of items allowed | 1 personal item + 1 carry-on bag (2 total) | 1 under-seat item + 1 overhead-bin item (up to 2, depending on fare and options) | 1 personal item + 1 carry-on bag (2 total) |
| Combined weight | Within 7kg | Within 7kg (applies to Starter, Starter Plus, and Starter Max fares, combined total of both bags) | Within 10kg |
| Carry-on bag size | Total of three dimensions within 115cm (each side within 55 x 40 x 25cm, including wheels and handles) | Under-seat: within 40 x 30 x 20cm / Overhead bin: within 56 x 36 x 23cm (48 x 34 x 23cm on Q300 aircraft) | Total of three dimensions within 115cm (each side within 55 x 40 x 25cm) |
| Personal item | Must fit under the seat in front (handbag, camera, umbrella, etc.) | Folded into the under-seat item category, no separate rule | Must fit under the seat in front (handbag, shoulder bag, etc.) |
The biggest practical difference lies in how weight is assessed versus how size is assessed. Peach and Skymark use a single "115cm total" framework and simply apply different weight caps on top of it. Jetstar Japan, on the other hand, sets different allowed dimensions depending on where the bag is stowed (under the seat or overhead).
Peach Aviation: A 7kg Cap and the 115cm Size Rule
Peach Aviation allows one personal item and one carry-on bag, two items in total.
- Personal item: handbag, camera, umbrella, or similar item that fits under the seat in front
- Carry-on bag: the sum of the three dimensions (length + width + height) must be within 115cm, with each side no larger than 55 x 40 x 25cm; this measurement includes wheels and handles
- Weight: personal item and carry-on bag combined must be within 7kg
If a bag exceeds these rules, it will be switched to checked baggage and a fee will be charged on the spot. For wheeled suitcases, be sure to measure with the handle still attached, not retracted.
Jetstar Japan: Separate Rules for Under-Seat and Overhead Bags
Jetstar Japan (under the rules currently in effect as of August 2026) sets different allowed dimensions depending on where the bag is stowed.
- One bag that fits under the seat in front: within 40 x 30 x 20cm
- A bag placed in the overhead bin: within 56 x 36 x 23cm
- On Q300 flights, the smaller cargo hold reduces even the 56 x 36 x 23cm allowance to 48 x 34 x 23cm
- On Starter, Starter Plus, and Starter Max fares, passengers may bring up to two bags, with the combined weight of both within 7kg
Starting February 2, 2027, the rules will be overhauled entirely. Economy bookings will, by default, include only one under-seat item (40 x 30 x 20cm); to add one overhead-bin item (56 x 36 x 23cm), for a total of two bags, passengers will need to select a priority carry-on option or a fare that includes it. Business bookings will include two bags by default from the start. Under this revised system, no separate weight cap will be specified; the size rule will apply in its place. If you're booking a flight departing on or after February 2027, be sure to check this new rule rather than the current 7kg rule.
Skymark: The Most Generous Terms, Allowing Up to 10kg
Skymark allows one personal item (handbag, shoulder bag, etc.) and one carry-on bag, two items in total.
- Carry-on bag size: total of three dimensions within 115cm, each side within 55 x 40 x 25cm (the same standard as Peach)
- Weight: personal item and carry-on bag combined within 10kg, 3kg more leeway than Peach or Jetstar Japan
That said, the rules specifically note that even if a bag stays within the size limits, it may still be refused if it's judged not to fit in the under-seat or overhead storage space, meaning actual measured size trips people up more often than weight does.
New Shared Rule Since April 2026: "Only Bags You Can Stow in the Overhead Bin Yourself"
On March 25, 2026, the Regular Airlines Association announced a new shared carry-on baggage rule for domestic Japanese airlines, which took effect on April 1, 2026 at the request of the Civil Aviation Bureau of the Ministry of Land, Infrastructure, Transport and Tourism, aimed at improving on-time performance.
- A new clause limiting personal items to a size that fits under the seat in front
- A new clause requiring that only bags of a size and weight the passenger can personally lift and stow in the overhead bin may be brought on board
- Applies to both domestic and international flights
This clause is a "conduct requirement" layered on top of each airline's existing numerical rules (115cm, 7 to 10kg, etc.). Even if a bag's size and weight are within the rules, it may still be refused if the passenger can't lift it into the bin alone, so if you plan to bring a heavy suitcase on board, check beforehand whether you can lift it by yourself.
Practical Checklist
- Measure your suitcase's three dimensions with wheels and handles included, and check it against each airline's limit (115cm total, or the separate under-seat and overhead dimensions)
- Weigh all your carry-on items together and confirm that the combined weight of your personal item and carry-on bag is within 7kg for Peach and Jetstar Japan, or 10kg for Skymark
- If flying Jetstar Japan, check whether your fare includes an overhead-bin bag, and if your departure date is on or after February 2, 2027, check whether the new rules apply
- Check in advance whether you can lift your suitcase into the overhead bin yourself (per the new clause introduced in April 2026)
- If there's a chance you'll exceed the limits, purchase checked baggage online in advance to avoid paying the higher fee at the airport
Reference: 機内持ち込み手荷物について | Peach Aviation
Reference: 【定期航空協会からのお知らせ】機内持ち込み手荷物に関するお願い | Peach Aviation
Reference: 機内持込手荷物 | ジェットスター
Reference: ジェットスター航空（JQ）の機内持込手荷物について（2027年2月2日改定） | ジェットスター
Reference: 機内持込手荷物｜手荷物｜スカイマーク SKYMARK
Reference: 機内持ち込み手荷物に関するお願い | 定期航空協会
Reference: 定期航空協会 機内持ち込み手荷物に関するお願い（PDF）