Michael Turner
Most major carriers set external limits very close to 56 x 36 x 23 cm; measure your piece fully zipped and include wheels, handles and any external pockets. Any single side larger than those figures may result in gate-checking or an oversize charge.
Budget operators often allow smaller external sizes. Common alternatives include 55 x 40 x 20 cm or other tighter boxes, and some impose strict weight caps. Verify the exact allowed external size and weight on the airline’s official site before travel.
Measure packed items with a tape measure and account for protrusions. Soft-sided cabin cases give a few millimetres of compression; rigid shells do not. If enforcement looks strict, remove bulky items or transfer them to a separate personal item that fits beneath the seat.
Practical rule: aim for a case at or below 56 x 36 x 23 cm for legacy and most international services, or choose ~54 x 34 x 20 cm to meet the strictest low-cost policies and avoid unexpected fees.
U.S. domestic airlines: cabin bag size limits
Recommendation: target 22″x14″x9″ (including wheels and handles) to fit overhead compartments on most major carriers; Southwest and Frontier permit up to 24″x16″x10″.
Quick reference by airline
- American Airlines – 22″x14″x9″ (wheels/handles included). One overhead item plus one personal item under seat. No published weight limit for onboard items.
- Delta Air Lines – 22″x14″x9″ (wheels/handles included). Overhead plus personal item allowed. No published weight cap.
- United Airlines – 22″x14″x9″ (wheels/handles included). Overhead and personal item permitted. No weight restriction listed for cabin pieces.
- Alaska Airlines – 22″x14″x9″. Overhead plus personal item; measure with handles/wheels.
- JetBlue – 22″x14″x9″. Overhead allowance and one personal item; no weight limit stated.
- Southwest Airlines – 24″x16″x10″. Two free pieces: one overhead bag plus one personal item under seat.
- Spirit Airlines – 22″x18″x10″ for overhead pieces (fee usually required); personal item maximum 18″x14″x8″ and is free.
- Frontier Airlines – 24″x16″x10″ for overhead pieces (fees often apply); personal item maximum 18″x14″x8″ free.
- Hawaiian Airlines – 22″x14″x9″ for cabin pieces; check international routes for different rules.
- Allegiant Air – 22″x14″x9″ for overhead pieces; an onboard fee may apply depending on fare and booking.
Exceptions, packing tips and enforcement
- Measurements normally include wheels, handles and any external pockets; measure end-to-end and corner-to-corner.
- Gate agents may require oversized items to be checked at the gate – expect a fee with low-cost carriers that charge for overhead access.
- No standardized weight limit across U.S. domestic carriers; however, extremely heavy items may be denied for stowage safety.
- Pack a compliant personal item (typical maximum ~18″x14″x8″) for essentials if an overhead fee applies or bins fill.
- Confirm specific dimensions and fee policy on the airline’s official site before departure; policies are periodically updated.
Major international carriers – typical cabin bag allowances
Aim for an external dimension under 56″ x 45″ x 25″ to cover the most permissive international policies; a safer target for broad compliance is 55 x 40 x 23 cm (≈21.7″ x 15.7″ x 9.1″) or 55 x 35 x 25 cm (≈21.6″ x 13.8″ x 9.8″).
Europe & UK examples
Common standards used by legacy European operators: 55 x 35 x 25 cm (≈21.6″ x 13.8″ x 9.8″) and 55 x 40 x 23 cm (≈21.7″ x 15.7″ x 9.1″). British Airways typically publishes 56 x 45 x 25 cm (≈22″ x 17.7″ x 9.8″) as its main cabin allowance and also permits one smaller personal item. Ryanair’s no-priority allowance is usually a compact under-seat item (roughly 40 x 20 x 25 cm, ≈15.7″ x 7.9″ x 9.8″), while priority boarding adds a larger bag allowance near 55 x 40 x 20 cm (≈21.7″ x 15.7″ x 7.9%).
Middle East, Asia-Pacific and other long-haul carriers
Major Middle Eastern and Asian carriers commonly use a 55 x 38 x 20 cm band (≈21.6″ x 15″ x 7.9″) or a 55 x 40 x 23 cm standard; Emirates often lists 55 x 38 x 20 cm as its cabin allowance, Lufthansa Group and several Star Alliance partners use 55 x 40 x 23 cm, and some full-service carriers accept up to 56 x 45 x 25 cm for premium cabins. Many airlines also impose a weight limit for the bag itself (typical range 7–10 kg / 15–22 lb) and allow a separate personal item for under-seat storage (common dimensions ~40 x 30 x 15 cm / ≈15.7″ x 11.8″ x 5.9″).
Practical recommendations: measure external dimensions including wheels and handles; label your bag with its dimensions or keep a tape measure in your travel kit; verify the exact policy on the carrier’s website within 72 hours before departure; pack a smaller under-seat item to avoid gate checks; be prepared for stricter enforcement on smaller aircraft and low-cost carriers, which often gate-check oversized items for a fee.
Measure a cabin bag including wheels and handles
Measure total external dimensions with wheels and the telescoping handle fully retracted; aim for 22″×14″×9″ or smaller for most U.S. airlines and check airline pages for exceptions.
Tools
Use a rigid tape measure (not cloth), a flat floor, and a level surface. Have a notebook or phone to record each dimension and a second person if available to hold the bag upright.
Step-by-step method
Stand the bag upright on its wheels. Measure height from the floor to the highest point of the bag with the handle down; include any wheel housings or fixed feet. Record that number as H.
Measure width across the front face at the widest point, including side pockets and external straps. Record as W.
Measure depth from front face to back face at the deepest point, including wheel protrusion and any bumpers. Record as D.
When an airline lists maximum allowed as 22″×14″×9″, compare H×W×D to those values; if any single dimension exceeds the limit, the bag risks gate-check. Allow a 0.5″ to 1″ margin for measurement error and zipper compression.
For soft-sided bags, measure when packed as you intend to travel; for hard-shell cases measure with contents in place and pressure applied to the shell as during handling. If the telescoping handle does not fully stow flush, measure with it stowed and again extended to confirm compliance for storage stowage rules.
If uncertain, measure the bag twice and verify the manufacturer’s published external dimensions; print or screenshot the airline size policy to show gate agents if needed.
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When an onboard bag is checked or gate-checked: size thresholds and fees
Keep your cabin item within the airline’s published limit; if any external dimension exceeds the limit by roughly 2–5 cm, expect it to be tagged for gate-check or refused in the cabin.
Concrete threshold triggers
Soft tolerance: most legacy carriers allow a 1–2 cm margin at sizers; low-cost carriers enforce limits to the millimeter. Oversize for checked items begins at a total linear dimension (length + width + height) above 158 cm (approximately 62″); exceeding that typically moves the piece into oversize category with separate charges. If weight limits for cabin items (commonly 7–10 kg on short-haul international or 8–12 kg on some regional ops) are exceeded, staff will usually require check or gate-check regardless of external size.
Fee ranges and practical steps
Fee patterns: domestic U.S. carriers charge about $30–35 for the first checked bag and $40–45 for the second; low-cost carriers often levy a higher penalty if a bag is handed at the gate, typically $60–200 depending on route and moment of payment. Oversize surcharges are commonly $100–200 per piece. International carriers vary: some include one checked item in fare classes, others apply per-kilogram or fixed oversize fees on top of base checked rates.
Recommendations: measure and weigh with wheels and handles extended, compare to the airline’s exact published figures, and prepay a checked allowance online if your bag exceeds cabin limits by any margin–online rates are generally $10–40 cheaper than gate transactions. Use a soft-shell case to squeeze into sizers, remove items at the gate to meet weight limits, and keep valuables and essentials in a permitted personal item to avoid disruption if your bag is routed to the hold.
Packing strategies to stay within size limits and increase usable space
Pick a soft-sided, rectangular bag whose exterior measurements are about 2–3 cm smaller than the airline’s permitted maximum; that margin prevents zipper bulge or handle protrusion from pushing you over the limit while preserving the largest internal volume.
Compression and organization
Use three types of organizers: (1) compression packing cubes sized to fill the main compartment (example cube set: 35×25×8 cm, 30×20×10 cm, 25×15×6 cm), (2) a thin zip pouch for documents and flat electronics, (3) one waterproof pouch for toiletries. Roll T-shirts and underwear into the largest cube, fold dress shirts flat into the medium cube, and reserve the smallest cube for intimates and chargers. Place the densest packed cube at the base so the bag keeps a rectangular profile; soft items around edges maintain straight sides for maximal usable space.
Replace liquid toiletries with solids (bar shampoo, toothpaste tabs) or decant into 100 ml refillable bottles; store them in a single clear pouch near the top for quick removal. Swap bulky sweaters for high-warmth, low-bulk merino or a lightweight down jacket that you wear during transit to free interior space.
Bulky items, footwear and odd shapes
Stuff shoes with socks, belts or small electronics to use void space and protect footwear. Pack shoes along one side rather than stacked to preserve a flat packing field. For odd-shaped items such as umbrellas or tripods, break them down to the shortest possible configuration and place along the bag’s corner so they don’t force the shell to bulge; if the item is a beach umbrella, collapse it and consult best material for deck umbrella and best way tosecure umbrella to sand for selection and securing tips.
Limit expansion reliance: use expandable zippers only as a contingency. If weight matters, use a travel scale and pre-weigh packed items; move heavy objects into a secondary permitted personal bag to keep the main bag within both dimensional and mass limits. Final adjustment: compress or redistribute content so all faces stay flat and corners remain square–that preserves fitted volume without exceeding airline measurements.
