The book giant said the breaches occurred at 63 stores in nine states. At least six of those stores are located in Southern California.
The hackers stole the information from the PIN pads at the cash registers. The affected stores have since removed those pads.
If you used a credit or debit card at Barnes & Noble recently, you should check your statement and change your PIN number.
B&N said it's working with federal law enforcement and with banks, payment card brands and issuers to identify accounts that may have been compromised, so that additional fraud-protection measures can be taken.
List of affected stores in California:
4735 Commons Way, Calabasas 2470 Tuscany Street, Corona 2015 Birch Road, Chula Vista 313 Corte Madera Town Center, Corte Madera 604 Bay Street, Emeryville 810 West Valley Parkway, Escondido 1315 E. Gladstone Street, Glendora 5183 Montclair Plaza Lane,Montclair 894 Marsh St., San Luis Obispo 2615 Vista Way, Oceanside 72-840 Highway 111, Palm Desert 27460 Lugonia Ave., Redlands 1150 El Camino Real, San Bruno 10775 Westview Parkway, San Diego 3600 Stevens Creek Blvd., San Jose 11 West Hillsdale Blvd., San Mateo 9938 Mission Gorge Road, Santee 40570 Winchester Rd., Temecula 4820 Telephone Road, Ventura 1149 S. Main St., Walnut Creek
List of affected stores in Connecticut:
470 Universal Drive North, North Haven 100 Greyrock Place, Stamford 60 Isham Road, W. Hartford
List of affected stores in Florida:
18711 NE Biscayne Blvd, Aventura 333 N. Congress Avenue, Boynton Beach 152 Miracle Mile, Coral Gables 1900 W. International Speedway, Daytona Beach 2051 N. Federal Highway, Fort Lauderdale 12405 N Kendall Drive, Miami 11380 Legacy Ave., Palm Beach Gardens 14572 SW 5th St., Pembroke Pines 11820 Pines Blvd., Pembroke Pines 5701 Sunset Drive, S. Miami 700 Rosemary Ave., West Palm Beach
List of affected stores in Illinois:
1441 West Webster Avenue, Chicago 1130 North State Street, Chicago 5380 Route 14, Crystal Lake 20600 North Rand Road, Deer Park 728 North Waukegan Road, Deerfield 1630 Sherman Avenue, Evanston 1468 Springhill Mall Blvd, W. Dundee
List of affected stores in Massachusetts:
170 Boylston Street, Chestnut Hill 96 Derby Street, Hingham 82 Providence Highway, East Walpole
List of affected stores in New Jersey:
395 Route 3 East, Clifton 55 Parsonage Road, Edison 2134 State Highway 35, Holmdel 4831 US Highway 9, Howell
List of affected stores in New York:
23-80 Bell Blvd., Bayside 176-60 Union Turnpike, Fresh Meadows 1542 Northern Blvd., Manhasset 160 E. 54th Street, New York 2289 Broadway, New York 33 East 17th Street, (Union Square) New York 555 Fifth Ave., New York 2245 Richmond Ave., Staten Island 230 Main St., White Plains 97 Warren Street, New York
List of affected stores in Pennsylvania:
100 West Bridge Street, Homestead 800 Settlers Ridge Center Drive, Pittsburgh
List of affected stores in Rhode Island:
1311 West Main Road, Middletown 371 Putnam Pike, Smithfield 1350-B Bald Hill Rd., Warwick
The Associated Press contributed to this report.