Best Bag Dimensions for Ryanair: 40×20×25 vs 55×40×20 cm

Ryanair's baggage policy is one of the most frequently misunderstood in European aviation. Unlike most airlines, which operate a single carry-on allowance, Ryanair has two distinct bag tiers with different size limits, different storage locations, and different costs. Getting this wrong at the gate is one of the most avoidable travel expenses there is.

Ryanair's Two Bag Tiers Explained

Tier 1: The Free Small Personal Bag (40×20×25 cm)

Every Ryanair ticket — regardless of fare type — includes one small personal bag. The dimensions are:

• 40 cm long
• 20 cm wide
• 25 cm tall

This bag must fit under the seat in front of you. It cannot go in the overhead bin. The 20 cm width is the key constraint — this is the height measurement when the bag is on the ground, and it determines whether the bag slides under the seat.

What fits in a 40×20×25 cm bag?

This is a relatively small allowance — roughly 20 litres. You can comfortably pack:

• 2–3 days of clothes (using packing cubes)
• A laptop and basic accessories
• Toiletries bag (liquids in 100 ml containers)
• Light shoes or a small pair of trainers

It's a realistic allowance for a short weekend trip with careful packing. For longer trips or trips requiring more gear, you'll need Tier 2.

Tier 2: The Cabin Bag (55×40×20 cm) — Requires Priority

The larger cabin bag is what most travelers mean when they say "carry-on." It goes in the overhead bin and holds roughly 40 litres. The dimensions are:

• 55 cm long (height when upright)
• 40 cm wide
• 20 cm deep

To bring this bag into the cabin, you must have one of the following:

1. Priority Boarding (purchased as an add-on or included in a higher fare)
2. A Ryanair cabin bag add-on purchased separately

Without one of these, your cabin bag will be checked at the gate into the hold — and you'll pay the gate check fee (currently up to €60 per bag).

How Much Does Priority Boarding Cost?

Priority Boarding pricing varies by route, how far in advance you buy, and any Ryanair promotions at the time. Approximate ranges:

• Booked at time of purchase: approximately €6–€18 per flight
• Added online later: approximately €10–€25 per flight
• At the airport: typically not available — you'll face the gate check fee instead

Priority Boarding includes:

• Early boarding (before standard passengers)
• The 55×40×20 cm cabin bag in the overhead bin
• Faster access to overhead bin space

For most travelers, adding Priority Boarding during the original booking is the most cost-effective choice if you plan to bring a cabin-sized bag.

Priority Boarding vs. Cabin Bag Add-On

Ryanair sometimes offers a cabin bag add-on that grants the right to bring a 55×40×20 cm bag without including the early boarding benefit. Prices are similar to Priority Boarding. The functional difference:

• Priority Boarding: early boarding + overhead cabin bag
• Cabin Bag Add-On: overhead cabin bag only (boards with standard group)

For most passengers, Priority Boarding is the better option since early boarding secures overhead bin space — a genuinely valuable benefit on full Ryanair flights.

Which Ryanair Fares Include Cabin Bags?

Ryanair's fare tiers (as of 2026):

Fare Type	Small Bag (40×20×25)	Cabin Bag (55×40×20)
Value	Included	Not included
Regular	Included	Not included
Plus	Included	Included
Flexi Plus	Included	Included

Value and Regular fares — the most commonly booked — do not include the overhead cabin bag. If you've booked one of these fares and need a cabin bag, add Priority Boarding or the cabin bag add-on during booking or afterwards through Manage My Booking.

How to Measure Your Bag for Ryanair

Ryanair uses physical metal bag sizers at the gate. The sizer is a rigid frame matching the exact allowed dimensions. Your bag must fit inside it without forcing. Here's how to check at home:

For the free small bag (40×20×25 cm):

1. Pack the bag fully
2. Measure the longest dimension — must be 40 cm or less
3. Measure the narrowest dimension (width) — must be 20 cm or less
4. Measure the remaining dimension (depth/height) — must be 25 cm or less
5. Check that no exterior pockets, handles, or accessories push beyond these dimensions

For the cabin bag (55×40×20 cm):

1. Pack the bag fully
2. Measure height (longest dimension when upright) — must be 55 cm or less
3. Measure width — must be 40 cm or less
4. Measure depth — must be 20 cm or less

Important: measurements include everything — exterior pockets, handles, wheels, and anything attached to the outside. A bag that is 20 cm deep but has exterior pockets that add 3 cm will not fit the sizer.

Common Bags That Fit the 40×20×25 cm Allowance

Several popular bags are specifically designed to fit under-seat personal item allowances at budget airlines. Bags in the 15–20 litre range with dimensions close to 40×20×25 cm include many slim backpacks and structured tote bags. Key characteristics to look for:

• Total capacity of 15–22 litres
• Soft sides (important for fitting the 20 cm width)
• No rigid external frame
• External pockets that compress flush with the main compartment

Many travel-focused slim backpacks hit these dimensions exactly or within a centimetre.

Common Bags That Fit the 55×40×20 cm Cabin Bag Allowance

The 55×40×20 cm format is narrower in depth (20 cm) than the standard IATA-recommended carry-on dimensions. Some bags marketed as "carry-on" sized are 22–25 cm deep and won't fit Ryanair's sizer. Bags that reliably fit include:

• Bags specifically marketed as "Ryanair-compliant" cabin bags
• Most soft-sided cabin bags with 35–40 litre capacity
• Rolling cabin cases from brands that publish Ryanair-specific dimensions

Hard-shell rolling suitcases are the highest-risk category — the rigid shell allows no compression, and if a hard case is 21 cm deep, it won't pass Ryanair's 20 cm gate sizer.

Which Tier Makes Sense for Your Trip?

Choose Tier 1 (small bag, free) if:

• You're traveling for 1–3 days
• You can fit everything in 20 litres
• You want to minimize total trip cost
• You're a frequent packer comfortable with traveling light

Choose Tier 2 (cabin bag, Priority Boarding) if:

• You're traveling for 4+ days
• You need to carry equipment (camera, laptop, sports gear, etc.)
• You want the flexibility of a full 40-litre bag
• You value overhead bin access and early boarding

Cost comparison example (Paris–Barcelona round trip):

• Fare only: €30 × 2 = €60
• Adding Priority Boarding round trip: approximately €15–€25 each way × 2 = €60–€100 additional

For a weekend trip where you can pack into the free 40×20×25 cm bag, saving €60–€100 is significant. For a longer trip where the cabin bag is genuinely needed, the add-on is still almost always cheaper than the gate check fee.

Tips for Ryanair's Strictest Enforcement

Ryanair is known for active enforcement at gates. Staff use physical sizers and will pull bags from the line if they appear oversized. To avoid problems:

• Add the appropriate option before you arrive at the gate. Ryanair's gate staff cannot add Priority Boarding — you'll simply be charged the gate check fee.
• Don't overstuff your bag. A technically-compliant bag that is visibly bulging may still be flagged. Pack so the bag maintains its shape.
• Travel in groups? Everyone needs their own Priority Boarding if they each have a cabin bag.
• Check Manage My Booking the night before. Confirm your Priority Boarding is showing correctly on your boarding pass.

The Bottom Line

Ryanair's baggage system has two tiers: a free small bag (40×20×25 cm, under the seat) and a larger cabin bag (55×40×20 cm, overhead) that requires Priority Boarding or a paid add-on. The free tier is a realistic allowance for short trips with careful packing. For longer trips, add Priority Boarding at booking — never at the gate.