Which backpack is allowed free of charge under the airplane seat?
- 7 min reading time
Choose an underseat backpack based on actual outside dimensions, packed depth, and your ticket. Compare the 45 cm and 40 cm limits correctly.
Short answer: a backpack may count as a free bag under the seat if its packed external dimensions, weight, and the number of bags fall within your ticket's allowance. Do not choose based on liters or the word “cabin,” but on the total size including shoulder straps, handle, and filled pockets.
Want to see the airlines side by side? View the current comparison of free underseat luggage for Ryanair, Transavia, easyJet, and Wizz Air.
What backpack size currently applies to budget airlines?
Checked on October 21, 2026. Ryanair, Transavia, and Wizz Air state a maximum of 40 × 30 × 20 cm for the small item under the seat. easyJet states 45 × 36 × 20 cm, including handles and wheels. Transavia and Wizz Air state a maximum of 10 kg; easyJet states a maximum of 15 kg, and you must be able to carry the bag yourself.
Before departure, read the current Ryanair, Transavia, easyJet, or Wizz Air page and check what is stated for your fare. Larger cabin luggage for the overhead compartment is a different category and may require payment.
Choosing a true underseat backpack
Pay attention to the full external dimensions and not just the capacity in liters. Two backpacks with the same number of liters can have very different shapes. A long, narrow bag, for example, may fit within easyJet's 45 cm limit but be too tall for a 40 cm limit. A deep backpack may conversely get stuck due to a filled front pocket.
- Height: measure from the bottom to the highest point of the packed bag.
- Width: include side pockets and protruding buckles.
- Depth: measure the thickest point, even if it is at the front pocket.
- Loose parts: tuck shoulder straps and straps inside the outline or include them in the measurement.
Measure the backpack after packing it. The full step-by-step method is explained in Measuring Hand Luggage: How to Check a Packed Underseater.
Travel backpacks in different sizes
Compare the stated dimensions with your booking. A backpack that is 45 cm high does not automatically fit within every underseat limit.
Trizand
20-Liter Travel Backpack
Black backpack measuring 40 × 25 × 20 cm with a main compartment, two additional pockets, and adjustable straps.
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View this product
MONOO
Black Backpack 45 × 32 × 15 cm
Travel backpack with a padded back panel, adjustable shoulder straps, and multiple zippered compartments.
View current price
View this product
The current Seprio backpack: which limit is it relevant for?
The black underseat backpack is listed in the catalog as 45 × 32 × 15 cm. This falls numerically within easyJet's current limit of 45 × 36 × 20 cm. For Ryanair, Transavia, and Wizz Air, the longest catalog dimension of 45 cm is larger than their current limit of 40 cm. Therefore, do not use this model for a 40 × 30 × 20 recommendation.
Even for easyJet, checking is still necessary: pack the backpack, measure the actual exterior, and check your booking. The size is a catalog specification and not a personal physical test or guarantee from the airline.
Backpack or soft travel bag under the seat?
A backpack keeps your hands free and distributes the weight over two shoulders. This is convenient if you are walking a lot or combining travel by train and plane. A soft travel bag often has a wide opening and can be placed horizontally more easily, but it is carried differently and can bulge out when a side pocket is full.
For a 40 × 30 × 20 limit, Seprio currently does have soft travel bags in its range. View those only as an alternative for shape, not as backpack advice, via Underseat Travel Bags. Also read when a weekend bag can count as free hand luggage for specific considerations.
Compare the backpack with the other models in easyJet underseat bags. Are you specifically looking for a soft bag within the 40 cm limit? Then view the selections for Ryanair, Transavia, or Wizz Air.
How to pack a backpack without adding extra centimeters
- Fill the main compartment first and leave elastic side pockets empty if they fall outside the dimensions.
- Place flat items against the back panel and prevent a bulging front pocket.
- Roll up loose shoulder straps or tuck them inside the outline of the bag.
- Do not use an expandable zipper if it exceeds the allowed depth.
- Measure again after adding a jacket, shoes, or purchases.
What to keep within reach during the flight
A bag under the seat is practical for documents, medication, and electronics that you need during the journey. Keep heavy items close to your back while carrying and do not block a zipper with loose cables. Make sure the bag can be placed completely under the seat and follow the instructions of the crew; an emergency exit row or specific seat may have different storage instructions.
Common mistakes
- automatically viewing a “cabin backpack” as a free personal item;
- measuring the empty backpack and then filling every compartment completely;
- confusing 45 cm with a 40 cm limit;
- only looking at liters;
- confusing larger paid cabin luggage with the free underseat bag;
- linking a travel bag as a recommended backpack.
Airline sources and product range checked on October 21, 2026. Product dimensions are catalog specifications; rules may change.