Stores are unveiling their plans for the most critical days of the holiday shopping season.

Here's a look at what major retailers have said about their hours for Thanksgiving Day and Black Friday. This list will be updated.

Barnes & Noble

Barnes & Noble stores will be closed on Thanksgiving. They'll be open from 8 a.m. to 10 p.m. on Black Friday. Online deals will be available starting on Thanksgiving.

Belk

Belk will open at 4 p.m. on Thanksgiving Day and will stay open until 1 a.m. Friday. The department store will reopen at 6 a.m. on Friday and remain open until 10 p.m.

Best Buy

Best Buy will open at 5 p.m. on Thanksgiving Day and will stay open until 1 a.m. Friday. Doors reopen that day at 8 a.m. and close at 10 p.m. A first round of deals will be available November 8-11.

Dick's Sporting Goods

Dick's stores will open at 6 p.m. on Thanksgiving and will remain open until 2 a.m. Friday. The stores will reopen at 5 a.m. that day and will remain open until 10 p.m.

GameStop

Many GameStop stores will be open on Thanksgiving, but none in Maine, Massachusetts or Rhode Island. Stores located in strip centers will be open 4 p.m. to 10 p.m. Stores located in malls will be opened during the mall's hours of operation. On Black Friday, stores located in strip centers will be open 6 a.m. to 10 p.m. and stores located in malls will be opened during the mall's hours of operation

JCPenney

JCPenney will open at 2 p.m. on Thanksgiving. Its stores will stay open until 10 p.m. the following day. Online sale prices will start four days ahead, on November 19.

Kmart

Kmart stores will open at 6 a.m. on Thanksgiving and will stay open until 10 p.m. on Black Friday. Some stores will close at midnight or 2 a.m. on Friday and reopen at 6 a.m.

Kohl's

Kohl's is opening at 5 p.m. on Thanksgiving and will stay open through 11:59 p.m. on Black Friday.

Lowe's

Lowe's stores will be closed on Thanksgiving Day. They will open at 6 a.m. on Black Friday.

Macy's

Macy's will open most of its full department stores at 5 p.m. on Thanksgiving. The company is also highlighting deals that will only be available at certain hours.

Neiman Marcus

Neiman Marcus stores will be closed on Thanksgiving, and open at 8 a.m. on Black Friday. Closing hours vary from store to store.

Office Depot

Office Depot and OfficeMax stores won't be open on Thanksgiving. Instead, doors will open at 7:45 a.m. on Friday. Online deals will start at 12:01 a.m. ET Thanksgiving Day.

PetSmart

PetSmart will be closed on Thanksgiving and will open on Black Friday from 7 a.m. to 9 p.m. Doorbuster deals will run from open until noon.

Sam's Club

Sam's Club opens at 7 a.m. on Black Friday, and the store says sales prices will be valid through that Sunday while supplies last. Online sales begin at midnight on Thanksgiving.

Sears

Sears says most of its stores will be open from 6 p.m. to midnight on Thanksgiving, though some will be closed for the holiday. All stores will reopen at 5 a.m. on Black Friday.

Target

Target's Black Friday event starts at 6 p.m. on Thanksgiving. New this year: Stores will close that night at midnight and reopen Friday at 6 a.m.

Toys "R" Us

Toys "R" Us will open its doors at 5 p.m. on Thanksgiving, and the store will stay open until 11 p.m. Friday. The company also has several pre-Black Friday deals offered through its catalog.

Walmart

Walmart's Black Friday sale begins at 6 p.m. on Thanksgiving in stores, and it will run all day online. The company is releasing color-coded maps of its stores to help customers find what they are looking for.

-- Danielle Wiener-Bronner contributed reporting to this story.