Allegiant personal item

Allegiant’s free personal item is 8 × 14 × 18 inches (20 × 35 × 45 cm), must fit under the seat, and is included on the base fare — the only free cabin bag by default. A larger bag or excess cabin item risks an at-airport fee ($50–$75 indexed — confirm live). A full-size carry-on (10 × 16 × 22 in) is a separate paid add-on (route/timing $10–$75; airport often $75). On Allegiant’s ULCC base fare, pack to the personal item unless you buy overhead space.

Compared with Frontier personal item (also ULCC-style free under-seat), Allegiant’s published free box is 8 × 14 × 18. Southwest and Delta typically pair a free personal item with a free carry-on on standard fares — Allegiant does not on the base fare.

• Personal item: free if within 8 × 14 × 18.
• Full carry-on: paid add-on (route/timing; airport often $75) — carry-on size / baggage fees.
• Checked: route-priced paid add-ons; published OW/OS +$50 / +$75 / +$75 — don’t duplicate full fee tables here.
• Also free when Allegiant states them (confirm the full list on the live baggage FAQ): car seats/strollers; mobility aids; medical equipment; food for in-flight; coat/jacket; diaper bag; umbrella.
• Military / loyalty waivers: confirm on allegiantair.com rather than assuming unpublished waivers.
• No named bag bundles — optional products in booking only if Allegiant currently labels them; don’t invent names.

1. Soft bags expand. A backpack that fits empty can fail 8 × 14 × 18 when packed — under-seat fit and enforcement care about the packed bag.
2. Oversized personal item → at-airport fee ($50–$75 indexed — confirm live), not “quietly allowed.”
3. Stale 7 × 15 × 16 popup — prefer 8 × 14 × 18 from CoC / /baggage-1 / Optional Services.
4. Do not confuse carry-on dims with personal item. Allegiant’s overhead max (10 × 16 × 22, paid) is larger — but base-fare flyers only get the smaller free bag for free.
5. Carry-on axis order differs from Frontier’s 24 × 16 × 10 — keep comparisons careful; see carry-on size.
6. No invented named bag bundles.

• Pack only a true under-seat bag on the base fare.
• Measure the packed bag (not empty marketing size) to 8 × 14 × 18.
• If you need overhead space, buy the carry-on early at booking (usually cheapest vs airport $75).
• Don’t wait until the airport or gate.

Shop for under-seat backpacks and slim totes marketed at or under 8 × 14 × 18 inches, then tape-measure the packed bag. Angle: bags that fit Allegiant’s personal item / under-seat size.

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

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

What is the Allegiant personal item size?
8 × 14 × 18 inches (20 × 35 × 45 cm). Must fit under the seat. Prefer this over older 7 × 15 × 16 popup text — confirm on the live site.

Is a personal item free on Allegiant?
Yes — one free personal item within size on the base fare. Full carry-on is a paid add-on.

What if my personal item doesn’t fit?
Oversized / excess cabin bags can incur an at-airport fee ($50–$75 indexed — confirm live). Measure ahead.

Does Allegiant allow a backpack as a personal item?
Yes if it fits 8 × 14 × 18 under the seat when packed (official examples include small backpack).

What’s the difference between Allegiant personal item and carry-on?
Personal: 8 × 14 × 18, free, under seat. Carry-on: 10 × 16 × 22, overhead — paid (route/timing $10–$75; airport often $75).

How does Allegiant compare to Frontier / Southwest / Delta?
Allegiant and Frontier are ULCC-style (personal free; carry-on often paid on the base/Basic fare). Southwest and Delta typically include a free carry-on on standard fares — confirm on those pages.

Confirm sizes and fees on allegiantair.com before travel. BagRule is not affiliated with Allegiant Air.