Best Buy on Tuesday announced that it will join Toys R Us and J.C. Penney by opening at 5 p.m. on Thanksgiving Day. That's one hour earlier than Target , Sears , Kohl's and Macy's , which will all open at 6 p.m. Thursday. Those four stores opened at 8 p.m. last year.

People enter Macy's Herald Square as the store opens its doors at 8 pm Thanksgiving day on November 28, 2013 in New York City.

Belk department store and Staples will also open two hours earlier than in 2013, at 6 p.m. on Thanksgiving, while RadioShack will open at 8 a.m. that day. Although the electronics chain had initially announced it would stay open through midnight on Thanksgiving, it later backtracked, saying it would close at noon on and reopen at 5 p.m.

Stores aren't just opening early—many are in it for the long haul. Belk will stay open until 10 p.m. on Black Friday. Sears and its Kmart unit, Kohl's, and Toys R Us will also host marathon hours; Kohl's will stay open through midnight Friday, while Sears will remain open through 10 p.m. that day. Kmart will stay open for 42 straight hours, beginning at 6 a.m. on Thanksgiving. That's one hour longer than last year. Toys R Us will close at 11 p.m. on Friday.

Macy's spokeswoman Holly Thomas said that last year, its flagship Herald Square store broke its record for a Thanksgiving weekend opening, with 15,000 people waiting at the doors. It was the first time the department store opened on Thanksgiving Day; in 2012, it opened at midnight on Black Friday.

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Sears Senior Vice President Leena Munjal said the retailer has also seen demand from shoppers who like to start early.

"This holiday season is all about giving more to our members and because many like to start shopping well before Black Friday, we're excited to open our doors early on Thanksgiving," she said.

Experts have stressed the importance of retailers catering to shoppers' desire to head to the mall when they finish Thanksgiving dinner. By opening early, companies can not only grab an early share of customers' wallets, but they can also build loyalty for the season—and perhaps get them to increase their budgets as the calendar gets closer to Christmas.

The Thanksgiving shopping trend is only exacerbated by online. According to PwC's Holiday Outlook study, 49 percent of shoppers plan to browse online to research products and make purchases on Thanksgiving morning.

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Still, a hefty amount of retailers are not folding to the pressure. Nordstrom will once again remain closed on Thanksgiving Day, as will GameStop, BJ's Wholesale Club and Sam's Club. Saks and Dillard's will also keep their doors shut on Thanksgiving, before opening at 8 a.m. on Black Friday. Costco will also be closed on Thursday, and will open at 9 a.m. on Black Friday.

Home improvement stores Lowe's and Home Depot will be closed on Thursday, and will open their doors at 5 a.m. on Friday. TJX said the majority of its T.J.Maxx and Marshall's stores will open at 7 a.m. Friday, though a few will open at 5 a.m. that day. Its HomeGoods stores will open at 7 a.m.

"We consider ourselves an associate-friendly company, and we are pleased to give our associates the time to enjoy the Thanksgiving holiday with family and friends," TJX spokeswoman Doreen Thompson said.



At the time of the Macy's announcement, Thomas said the majority of its Thanksgiving Day shifts had been filled voluntarily. She said the company received feedback last year that many of its employees "appreciated the opportunity to work on Thanksgiving so they could have time off on Black Friday," as well as the additional pay they receive for working a holiday. For any shift that begins on Thursday, employees will be paid time-and-a-half.

Macy's announced last month that it will hire 86,000 seasonal workers this holiday, an increase of about 3.6 percent compared to 2013. Kohl's also increased its holiday hiring this year, saying it will hire more than 6,700, up 1,700 from last year. Target said it will add 70,000 seasonal workers this year, the same as 2013.

Note: This story will be updated as other retailers announce their holiday hours.