Last updated: February 2026
Allegiant Air carry on size rules in 2026 require paid cabin bags to stay within 22 x 14 x 9 inches, while personal items must fit inside 16 x 15 x 7 inches. Allegiant is known for strict enforcement, especially at boarding gates.
This complete guide explains Allegiant Air carry-on size limits, personal item dimensions, baggage fees, and how to avoid paying unnecessary gate charges.
Allegiant Air Baggage Overview (2026)
Allegiant operates a low-base-fare model:
- Base ticket includes one personal item only.
- Carry-on bags cost extra.
- Checked baggage costs extra.
- Fees increase closer to departure.
There is no free overhead carry-on included with basic fares.
Allegiant Personal Item Size (Free Allowance)
All Allegiant passengers may bring:
- 16 x 15 x 7 inches
- Must fit completely under the seat
- No published weight limit
- Must fit inside airport sizer
In centimeters:
- 40 x 38 x 18 cm
This is slightly different from Spirit and Frontier (which allow 18 x 14 x 8 inches).
The shorter depth (7 inches) can catch travelers off guard.
What Qualifies as a Personal Item?
Acceptable examples:
- Small backpack
- Compact laptop bag
- Small purse
- Slim travel tote
Not acceptable if oversized:
- Standard school backpack over 7 inches deep
- Expandable travel bag
- Small roller suitcase
If it does not fit fully in the sizer, it becomes a paid carry-on.
Allegiant Carry-On Size (Paid)
If you purchase a carry-on bag:
- 22 x 16 x 10 inches
- Must fit in overhead locker
- Weight limit: 40 lbs
In centimeters:
- 56 x 41 x 25 cm
Note: Width is slightly narrower than Spirit/Frontier (16 inches vs 18 inches).
Allegiant Carry-On Fees (2026)
Fees vary based on when you purchase.
Typical pricing:
- During booking: $18–$35
- After booking online: $35–$50
- Airport counter: $50–$75
- Gate purchase: $75+
Gate charges are significantly higher.
Always pre-purchase online.
How Strict Is Allegiant About Bag Size?
Allegiant is very strict.
Enforcement patterns:
- Sizers at boarding gate
- Agents actively monitor bag dimensions
- Oversized personal items charged immediately
- Limited discretion
While slightly less aggressive than Spirit, enforcement is consistent.
Assume your bag will be measured.
Allegiant vs Spirit vs Frontier Comparison
| Airline | Free Personal Item | Carry-On Size | Enforcement |
|---|---|---|---|
| Allegiant | 16 x 15 x 7 | 22 x 16 x 10 | Very Strict |
| Spirit | 18 x 14 x 8 | 22 x 18 x 10 | Extremely Strict |
| Frontier | 18 x 14 x 8 | 22 x 18 x 10 | Extremely Strict |
Allegiant’s free personal item depth (7 inches) is the tightest of the three.
Weight Enforcement on Allegiant
- Personal item: No official weight cap.
- Carry-on bag: 40 lb maximum.
Size enforcement is far more common than weight checks.
If your bag fits the sizer, weight is unlikely to be questioned unless visibly heavy.
What Happens If Your Bag Is Too Large?
If your personal item exceeds 16 x 15 x 7 inches:
- You will be directed to the sizer.
- If it does not fit, it becomes a paid carry-on.
- Gate fee applies.
- Bag is placed in overhead or hold.
Gate fees can exceed $75.
This is avoidable with proper measurement.
Boarding Groups and Overhead Space
Allegiant boards in zones.
Passengers who purchase carry-on board earlier.
Personal item-only passengers board later.
Overhead space is primarily allocated to paid carry-on bags.
Do not expect overhead access without payment.
Allegiant Personal Item Packing Strategy
Packing into 16 x 15 x 7 inches requires discipline.
You can realistically fit:
- 2 lightweight outfits
- Small toiletry kit
- Electronics
- Travel documents
Use:
- Compression packing cubes
- Slim-profile backpack
- Lightweight materials
Avoid thick, structured bags.
Carry-On vs Checked Bag Strategy
Allegiant offers competitive checked baggage pricing.
Sometimes:
- A checked bag costs similar to a carry-on.
- Checked bag provides more flexibility.
- Avoids cabin storage stress.
However:
- Checked bags require baggage claim wait.
- Add risk of delay.
Always compare total cost.
Aircraft and Cabin Space
Allegiant primarily operates:
- Airbus A320 family aircraft
Overhead space is structured for purchased carry-ons.
Personal item passengers should expect under-seat storage only.
Real-World Allegiant Scenario
Passenger arrives with backpack measuring 17 x 15 x 8 inches.
Depth exceeds 7-inch allowance.
Bag does not drop fully into sizer.
Agent charges $75 gate fee.
Lesson: The 7-inch depth rule is strictly applied.
Common Allegiant Carry-On Mistakes
- Ignoring 7-inch depth restriction.
- Using standard school backpack.
- Purchasing baggage at airport.
- Not measuring including wheels.
- Overfilling soft bags.
Allegiant enforces compliance consistently.
FAQ
What size personal item is free on Allegiant?
16 x 15 x 7 inches.
Is Allegiant strict about bag size?
Yes. Sizers are used at boarding gates.
Can I bring a carry-on for free?
No, unless included in a specific bundle.
Does Allegiant weigh carry-ons?
Carry-ons have a 40 lb limit, but size is enforced more than weight.
What happens if my bag is too big?
You will pay a gate fee and the bag becomes a paid carry-on.
Summary
Allegiant Air carry-on rules in 2026 allow one free personal item measuring 16 x 15 x 7 inches.
All larger bags require payment.
To avoid expensive airport fees:
- Use a compliant personal item.
- Pre-purchase carry-on online if needed.
- Measure including wheels and handles.
- Avoid overpacking.
Preparation is significantly cheaper than gate penalties.
Airlines That Charge for Carry On
Carry-on Weight Limits