The unbundling of cabin baggage: why your personal item is now the only free bag

Short answer: over the last decade airlines moved from "carry-on included" to "one free personal item, carry-on sold separately." The personal item — the small under-seat bag — is now the only thing most low-cost fares include for free. That is exactly why a personal item that fits every sizer, like a 25 × 17 × 14 cm bag, is worth more than its size suggests.

From bundled to à la carte

Legacy carriers still bundle a carry-on and a personal item. Low-cost carriers increasingly sell the carry-on as an add-on and keep only the under-seat personal item free. The shift is structural, not a one-off promotion.

Fare model	Free at the gate	Carry-on
Legacy (Lufthansa, American, United)	personal item + carry-on	included
Low-cost (Ryanair, Wizz, easyJet, Spirit)	personal item only	paid add-on

What the shift does to bag value

When the carry-on is paid, the free personal item stops being an afterthought and becomes the bag you actually travel on. A personal item that fits every sizer for free — no priority purchase, no gate fee — is the difference between a fare that includes a bag and one that does not.

The honest limit of the trend

Unbundling does not change any sizer dimension; it changes what is free. The 15 cm depth wall is unchanged. So the bag's job is the same as it always was — clear the strictest sizer — it just matters more now that the personal item is doing more of the work.

Should you buy the Jelkin 25 for this?

As the carry-on moved behind a paywall, the personal item became the only bag most low-cost fares include — so a personal item that clears every sizer is now worth more than its size suggests. The sizer dimensions did not change; what changed is how much work that one free bag has to do. Buy for the unbundled fare you are actually on.

How to check this yourself before you fly

1. Check what your fare includes free. On many low-cost tickets it is only the under-seat item.
2. Assume the carry-on is paid unless your fare says otherwise. That is the structural shift.
3. Make the free bag do more: it is no longer an afterthought, it is the bag you travel on.
4. The dimensions did not change. Clear 15 cm of depth and you are free on every carrier we track.

Keep reading:

• airline personal item size checker — all 19 carriers side by side
• one-centimetre depth cliff — why 15 cm decides six airlines
• the 25 cm bag that fits every sizer — length-vs-depth end to end
• why external dimensions lie about capacity — how we measure bags
• Jelkin 25 — the 25 × 17 × 14 cm bag measured on this page