You don't need to be a math whiz to see how quickly fees can add up. Here's a sampling of Spirit's extra charges.

Now, avoid accordingly.

Baggage

DomesticInternational

Online purchase

Carry-on bag

(At booking)$30$30

First checked bag

(At booking)$28$33

Carry-on bag

(At check-in)$35$35

First checked bag

(At check-in)$33$38

Airport counter/

kiosk purchase

Carry-on bag$40$40

First checked bag$38$43

Airport gate purchase

Bags checked at gate$45$45

Seating

Customer-requested seat assignments/deluxe leather $1 to $50

Big front seats (in advance) $12 to $199

Booking

Phone reservation booking fee (except to and from Colombia)

$10 per customer per booking

Passenger usage fee (domestic flights) $8.99 to $16.99 per

customer, each way

Check-in

Airport agent prints boarding pass $5 per pass

Print boarding passes at kiosk (starting June 30) $2 per pass

Food

Snacks $1 to $10

Drinks $1 to $15

Spirit Airlines announced last week that, come May 1, it will start flying out of Minneapolis-St. Paul International Airport. To start, it plans flights twice a day to Chicago's O'Hare and once a day to Las Vegas, but other destinations are under consideration. From Chicago, travelers can fly the airline to Ft. Lauderdale, Fla., which has connecting routes to Cancun, Mexico; several stops in the Caribbean, and cities in Central and South America. As part of its rollout at MSP, it will offer $9 base fares in June that will total $28.79 with fees and taxes. Spirit has crowned itself the "ultra" low-cost carrier, but the cost of a trip can climb with fees for incidentals. But with some simple strategies, you can easily nab a low-flying fare on Spirit. A few tips: • For online reservations, check the fares on third-party sites such as Kayak and Expedia to be sure that Spirit really has the lowest price. If it does, purchase the flight on the carrier's Website (www.spiritairlines.com) and you'll probably save at least $5 each way. To avoid paying the passenger usage and the "unintended consequences" fees, buy your ticket at the airport. • If you're a frequent traveler, consider joining the $9 Fare Club. The charge of $19.95 for a 60-day trial or $59.95 a year grants members access to exclusive deals and discounts on checked and carry-on bags. At the very least, sign up for e-mail promotions for no extra charge. Also, check the Website frequently for coupons and sales. • If you plan to check or carry on bags, pay in advance online, a cheaper alternative to paying at the airport counter or at the gate. Also be aware of your bags' weight and size: The airline charges an additional $25 for bags that weigh 41 to 50 pounds and $100 for those measuring more than 62 inches. And it just gets worse from there. • If you can pack light, try to cram all your belongings into a personal item that fits under the seat. There's no charge for this category of carry-on, and once you're settled in your seat, you can toss your bag into the overhead bin for free. • Unless you're picky or traveling as a family, don't preselect a seat; let the airline choose for you. At the last minute, however, I was able to switch my airline-assigned seat at the airport kiosk for no charge. • Bring all your own food and drinks onboard. Cold beverages, including soda and bottled water, purchased at the airport often cost less than the selection sold in-flight. WASHINGTON POST AND STAFF REPORT