Sun Country personal item

Sun Country’s free personal item (“Underseat item”) is 17 × 13 × 9 inches (H×W×D; ~43 × 33 × 23 cm), must fit under the seat, and is free — one per traveler on all reservations. A larger bag is treated as overhead (a paid add-on unless Military free overhead or a current Bundle Deal includes it). Underseat fit is enforced — measure the packed bag before you fly; soft expandable bags that push past 17×13×9 will not count as the free underseat item.

Field	Value
Max dimensions (in)	17 × 13 × 9 in (H×W×D) — official “Underseat item”
Max dimensions (cm)	~43 × 33 × 23 cm (converted; inches are primary)
Placement	Under the seat (not overhead)
Cost	Free — all reservations (one per traveler)
Weight	Not published as a separate underseat weight limit on the bags page — do not invent a lb limit
If oversized	Treated as overhead + applicable fee (dynamic — confirm in booking); gate may add +$10 Gate Handling Fee — baggage fees
Carry-on contrast	24 × 16 × 11 in, 35 lb; paid on the base fare — carry-on size
Allowed examples	Purse, backpack, duffel (if fits) — soft official examples
Base fare interaction	Base = underseat only for a free cabin bag
Sizer / enforcement	Must fit under the seat; overhead sizer at counter/gate for larger bags — measure packed bag before travel
Bundles	Optional Bundle Deals — confirm live if claiming bag inclusion

Compared with Avelo personal item (also 17 × 13 × 9), Sun Country matches that free underseat box. Breeze publishes 17 × 13 × 8 — do not copy Breeze’s shallower depth onto SY. All three are ULCC-style on the base fare: personal free, overhead usually paid.

• Personal (underseat): always free (one per traveler) within 17 × 13 × 9.
• Full overhead: paid add-on on the base fare (Military: 1 overhead free with ID) — carry-on size / baggage fees.
• Checked: dynamic paid unless Military (2× up to 100 lb) or card/bundle benefits.
• Mobility / medical devices: free per official page; not counted as overhead.
• Seats and Bundle Deals are separate products — confirm live if claiming bag inclusion.

1. Soft bags expand. A backpack that fits empty can fail 17 × 13 × 9 when packed — underseat fit cares about the packed bag.
2. Oversized personal item → overhead fee (booking → counter → gate ladder; gate +$10 handling) — not “quietly allowed.”
3. Do not confuse SY’s generous overhead dims (24×16×11) with the underseat free bag — base flyers only get the smaller free bag for free.
4. Same personal size as Avelo (17×13×9); Breeze is 17×13×8 — don’t copy Breeze depth.
5. Weight limit for underseat is not published separately — don’t invent one.
6. Bundle Deal names and bag inclusion — confirm on live booking only.

• Pack only a true underseat bag on the base fare.
• Measure the packed bag (not empty marketing size) to 17 × 13 × 9.
• If you need overhead space, buy early online or check current Bundle Deals (confirm live).
• Don’t wait until the gate (+$10 handling on top of the airport bag fee).

Shop for under-seat backpacks and slim totes marketed at or under 17 × 13 × 9 inches, then tape-measure the packed bag. Angle: bags that fit Sun Country’s underseat / personal item size.

Disclosure: As an Amazon Associate, BagRule may earn from qualifying purchases. Suggestions are optional — always verify against Sun Country’s published dims.

Fit goal	What to look for
Free Sun Country underseat item	External dims ≤ 17 × 13 × 9 in; fits under seat when packed
Paid overhead	≤ 24 × 16 × 11 in / 35 lb — see carry-on size

(Soft Amazon: up to 1–2 under-seat / sizer-fit product cards may be placed here in production. Keep fee discussion non-commercial.)

What is the Sun Country personal item size?
17 × 13 × 9 inches (H×W×D; ~43 × 33 × 23 cm). Must fit under the seat. Official label: Underseat item.

Is a personal item free on Sun Country?
Yes — one free underseat item per traveler on all reservations. Base fare does not include a free full-size overhead bag.

What if my personal item doesn’t fit under the seat?
It can be treated as overhead and charged the overhead fee (higher at the gate, with +$10 Gate Handling Fee). Measure ahead — baggage fees.

Does Sun Country allow a backpack as a personal item?
Yes if it fits 17 × 13 × 9 under the seat when packed (purse, backpack, duffel listed as examples if they fit).

What’s the difference between Sun Country personal item and carry-on?
Personal (underseat): 17 × 13 × 9, free, under seat. Overhead: 24 × 16 × 11, 35 lb — paid on the base fare (Military: 1 free).

How does Sun Country personal item compare to Avelo or Breeze?
SY and Avelo both publish 17 × 13 × 9; Breeze is 17 × 13 × 8. All three ULCC-style: personal free, overhead usually paid on base — see also Frontier and Allegiant.

Confirm sizes and fees on suncountry.com before travel. BagRule is not affiliated with Sun Country Airlines.