How to fit a weekend into the free under-seat bag

Both low-cost airlines flying from Sofia carry a 40 x 30 x 20 cm bag free on every fare, under the seat in front. That is roughly 24 litres, which is a normal daypack rather than a token pouch.

It is also more than the industry minimum. Airlines for Europe members committed in July 2025 to guarantee a free personal item of 40 x 30 x 15 cm, and both Ryanair and Wizz Air went past it by keeping 20 cm of depth.

The weight rules differ. Wizz Air allows up to 10 kg, which is generous enough that size, not weight, is what stops you. Ryanair publishes no weight limit for this bag at all and does not weigh it, so on Ryanair the entire test is whether the bag drops into the sizer.

This is the only zero-cost baggage outcome available on either airline. Everything else on this site is a purchase.

A large amount of luggage sold as cabin approved is cut to a size that no longer matches the rule.

Ryanair enlarged its free bag during 2025, from the older 40 x 20 x 25 cm shape to 40 x 30 x 20 cm. That is about a fifth more volume, and it happened quietly enough that retail listings, blog guides and some bag manufacturers still advertise the old spec.

Ryanair's own fare bundle article writes the same size with the axes in a different order, as 40 x 20 x 30 cm. That is the identical volume, not a different allowance, and it is another reason people think the rules disagree with themselves.

So ignore the words on the product page and read the three numbers. If a bag is sold at 40 x 20 x 25 cm you are buying about 20 litres when you are entitled to about 24, and paying for the privilege.

The measurement that matters is the one taken with everything in the bag.

Wizz Air's conditions of carriage state that the stated dimensions include side pockets, and exclude handles and wheels with no more than 5 cm allowed for the wheels. A soft bag that sits neatly at 40 x 30 x 20 cm empty can fail once the side pockets are full and the front panel bulges.

This is the single most common way a compliant bag becomes a non-compliant one, and it happens between your hallway and the gate.

A soft bag is the better choice for exactly this reason. It compresses into a sizer frame where a hard shell will not, and it forgives an extra jumper. If you already own a hard-shell case at the free size, pack it to leave the lid flat rather than straining.

Check it at home, packed, against a tape measure. It takes a minute.

Ryanair describes the free allowance as one small personal bag, such as a handbag or a laptop bag. The word doing the work is one.

A handbag and a laptop bag is two items and is not the Basic allowance. Neither is a backpack plus a duty-free-sized tote you brought from home. A genuine second piece requires Priority and 2 Cabin Bags, which is the product that carries the overhead trolley.

The fix is free and takes no planning: put the laptop inside the one bag. A 24-litre pack holds a 13-inch laptop flat against the 40 x 30 face and still leaves the depth for clothes.

Wizz Air's free allowance is also a single bag, at the same dimensions, with the difference that it carries a published 10 kg limit.

If you find yourself planning around two separate pieces on a Basic fare, you are already outside the allowance and it is cheaper to know now.

A short list of things that do not count against the allowance, and one that does.

Wizz Air publishes its list: a coat or a blanket, your mobile phone, reading material for the flight, and anything you buy airside after security. For a lap infant it adds food for the flight and a foldable stroller or small crib, and one pushchair per child is checked free of charge.

A neck pillow is not on that list. Wizz Air says so directly, and it has to fit inside the bag.

The coat is the useful one. On a winter weekend the coat is the single bulkiest item you own, and carrying it rather than packing it can be the difference between a bag that closes and one that does not.

Security rules on liquids are set at the airport rather than by the airline, so check the airport's own page for the departure you are taking.

Work backwards from the shape of the bag rather than from a list.

Wear the bulkiest layer and the heaviest shoes to the airport. That is the coat, the jumper and the boots, and it is worth several litres.

Pack one spare pair of shoes at most, and only if they are flat. Shoes are the item that ruins a small bag, because they do not compress and they do not stack.

Roll the soft things rather than folding them. Two changes of clothes plus one spare covers two nights and most of a third. Put the flat items, a laptop or a book, against the 40 x 30 face so they brace the bag rather than bowing it.

Keep documents, chargers and liquids in one pouch near the top, so the security tray does not force you to unpack the whole bag and repack it badly in a queue.

Two nights fits with room. Three fits in summer if you are disciplined. Past that the free bag stops being the right answer and pretending otherwise costs more than it saves.

The variable is almost always the weather rather than the days. A three-night trip to Rome in June is a smaller packing problem than a two-night trip to Vienna in January, because the January version needs a coat, a jumper and boots that are either on you or in the bag.

When the free bag will not do it, the next step is a purchase, and the cheapest one depends on the airline. On Ryanair the 10 kg trolley and the 10 kg hold bag are priced in overlapping bands, so check both. On Wizz Air the trolley starts lower, €10 against €15, but those bands overlap as well, so check both there too.

Knowing which side of that line your trip falls on is the useful part. It is a decision, not a squeeze.

The free bag is only free if it passes, and passing is mechanical.

Ryanair's gate sizer is a rigid frame and the bag is expected to drop into it unaided. Ryanair states plainly that a bag which does not fit will be refused at the boarding gate, or placed in the hold for a fee.

That fee is €70 to €75 on Ryanair and €55 to €65 on Wizz Air, per bag, per one-way flight. On Wizz Air the conditions of carriage let the airline carry the bag in the hold anyway, so you pay the charge and travel without it.

Enforcement has tightened rather than relaxed. Travel press through 2026 reported that Ryanair raised the bonus paid to gate staff for spotting an oversize bag to about €2.50 in November 2025 and removed the monthly cap. Ryanair has not confirmed those amounts, so treat the figure as reported, and the direction as the part to act on.

If you have read that the EU has banned cabin bag fees, the free under-seat bag is the part that is true.

The revised air passenger rights regulation cleared its final votes in July 2026 and applies roughly a year after publication, so around 2027. Per the European Parliament's own statement it guarantees free carriage of one personal item, and it obliges airlines and booking sites to show a fare inclusive of carry-on luggage from the start of the process.

It does not make the overhead trolley free. It expressly permits airlines to keep selling cheaper fares to passengers travelling without hand luggage.

And because Ryanair and Wizz Air already carry a 40 x 30 x 20 cm free item, larger than the minimum, neither has to change anything for you.

So packing to this size is not a temporary saving waiting to be regulated away. It is the outcome that stays free.