What is the Jetstar personal item size?

From February 2, 2027 on Jetstar Airways flights, the underseat bag can be up to 40 x 30 x 20 cm (about 16 x 12 x 8 in). Today, Jetstar publishes no size for the small item; it just has to fit under the seat in front of you.

Is there a weight limit for the Jetstar underseat bag?

Until February 2, 2027, your small item shares 7 kg with your main carry-on, and no bag can be over 10 kg. From that date, on Jetstar Airways flights, the 7 kg shared limit goes and the 10 kg cap per bag stays.

Can I bring a personal item and a carry-on on a Jetstar Starter fare?

Today, yes: 2 items with a combined 7 kg. From February 2, 2027, on Jetstar Airways flights, a Starter fare includes only the underseat bag; the overhead bag needs Priority Carry-on or the new Flex bundle.

Can a backpack be my Jetstar personal item?

Yes, if it fits under the seat in front of you. From February 2, 2027, it also has to be within 40 x 30 x 20 cm and 10 kg.

Does the underseat rule apply to Jetstar Japan?

No. Jetstar Japan flights keep today's 2 item, 7 kg rule.

I booked before August 5, 2026. Do I only get the underseat bag?

No. For flights from February 2, 2027 booked before August 5, 2026, Jetstar includes Priority Carry-on, so you also get an overhead bag. Group bookings are excluded.

Jetstar

Jetstar Personal Item

On Jetstar, the bag at your feet is about to matter much more. From February 2, 2027, on Jetstar Airways flights, it's the only cabin bag every fare includes.

Quick answer

Now: your second cabin item, such as a handbag or thin laptop bag, must fit under the seat in front of you. Jetstar publishes no size for it. It shares a 7 kg combined limit with your main carry-on.
From February 2, 2027, on Jetstar Airways flights: one underseat bag up to 40 x 30 x 20 cm (about 16 x 12 x 8 in, converted) is included with every booking. The 10 kg cap per bag, which already applies today, stays.
Anything bigger needs an overhead bag, which comes with Priority Carry-on or the new Flex bundle.
Jetstar Japan flights keep today's 2 item, 7 kg rule.

Verified November 13, 2026 against jetstar.com

Official sources: carry-on rules from Feb 2, 2027 · carry-on rules now · Jetstar newsroom: carry-on change. How we check: how we verify fees.

The small bag: now and from February 2, 2027

Swipe for more

Rule	Now	From February 2, 2027 (Jetstar Airways flights)
Your free small bag	Second cabin item, such as a handbag or thin laptop bag	Underseat bag, such as a handbag, laptop bag or small backpack
Size	Must fit under the seat; no size published	Up to 40 x 30 x 20 cm (about 16 x 12 x 8 in, converted)
Weight	Shares 7 kg with your main carry-on; no bag over 10 kg	Up to 10 kg
Other cabin bags included	Your main item (overhead)	None on a Starter fare

The 40 x 30 x 20 cm size applies only to the underseat bag from February 2, 2027. Jetstar doesn't give today's small item a size.

Extras on top of the underseat bag

Travelling with a baby: from February 2, 2027, you can take an extra underseat bag for baby items at no extra cost. Jetstar hasn't given a size for it. Today, an infant under two on your lap has no carry-on allowance of their own.
Duty free: from February 2, 2027, you can bring one small duty-free bag on board on top of your allowance, with proof of purchase. Until then, duty-free goods count as part of your small item.

For strollers, car seats and diaper bags across airlines, see our baby gear guide.

Which rules apply to you

The new rules follow your travel date: Jetstar Airways flights departing from February 2, 2027. Jetstar Japan flights and group bookings of 10 or more keep today's rules. If you booked before August 5, 2026 for a flight from February 2, 2027, Jetstar includes Priority Carry-on, so you still get an overhead bag (group bookings excluded).

Travelling with only the underseat bag

From February 2, 2027, a Starter fare means fitting everything into 40 x 30 x 20 cm. That's roughly a small backpack. A few things help:

Choose a soft bag and measure it packed. Rigid cases waste space in the corners.
Wear your bulkiest layer and shoes on the plane.
Keep liquids and chargers on top, so security checks don't mean unpacking everything.
Compare Priority Carry-on and a checked bag when you book. Both are priced per flight in the booking flow, and the gate is the most expensive place to fix a bag problem.

Not sure whether your bag counts as a personal item or a carry-on? Our personal item or carry-on guide explains the difference.

Gotchas

Under the seat means under the seat. A bag that doesn't fit there has to go in the overhead locker, which from February 2, 2027 needs Priority Carry-on.
10 kg is the cap per bag, today and from February 2, 2027, the underseat bag included.
A trip either side of the date has a different allowance on each flight.
Mixing Jetstar Airways and Jetstar Japan flights: pack for the smaller allowance.

FAQ

What is the Jetstar personal item size?: From February 2, 2027 on Jetstar Airways flights, the underseat bag can be up to 40 x 30 x 20 cm (about 16 x 12 x 8 in). Today, Jetstar publishes no size for the small item; it just has to fit under the seat in front of you.
Is there a weight limit for the Jetstar underseat bag?: Until February 2, 2027, your small item shares 7 kg with your main carry-on, and no bag can be over 10 kg. From that date, on Jetstar Airways flights, the 7 kg shared limit goes and the 10 kg cap per bag stays.
Can I bring a personal item and a carry-on on a Jetstar Starter fare?: Today, yes: 2 items with a combined 7 kg. From February 2, 2027, on Jetstar Airways flights, a Starter fare includes only the underseat bag; the overhead bag needs Priority Carry-on or the new Flex bundle.
Can a backpack be my Jetstar personal item?: Yes, if it fits under the seat in front of you. From February 2, 2027, it also has to be within 40 x 30 x 20 cm and 10 kg.
Does the underseat rule apply to Jetstar Japan?: No. Jetstar Japan flights keep today's 2 item, 7 kg rule.
I booked before August 5, 2026. Do I only get the underseat bag?: No. For flights from February 2, 2027 booked before August 5, 2026, Jetstar includes Priority Carry-on, so you also get an overhead bag. Group bookings are excluded.

Jetstar pages: Jetstar baggage allowance · Jetstar carry-on size Compare: Personal item size by airline · Carry-on size by airline Guides: Bags that fit strict airlines · Will my bag fit the sizer?

Disclaimer

Bag rules change. Confirm size, fee, and fare rules on the Jetstar site before you travel. BagRule is a publisher site and does not sell tickets or bags.