Starbucks announced a 2-for-1 stock split, with shareholders as of March 30 to get one additional share for each one they have. The change is the first split since October 2005 and the sixth one overall.
FedEx posted earnings that beat on revenue that was slightly below estimates. The company's full-year guidance was also slightly lower than expected, but its commentary was generally upbeat and analysts have pointed out that FedEx guidance tends to be on the conservative side.
General Mills reported adjusted quarterly profit of 70 cents per share, 3 cents above estimates, with revenue also beating Street consensus. The cereal maker and food producer said it expects to continue "strong growth" during the current quarter.
Williams-Sonoma, Guess and Cintas are all due to report after the bell.
Alibaba's share lock-up expires on Wednesday, allowing the Chinese e-commerce and web conglomerate to sell up to 437 million of its shares.
Apple is scheduled to replace AT&T in the Dow Jones industrial average on Wednesday after the bell, as Visa implements a 4-for-1 stock split.
American Airlines will replace Allergan in the S&P 500 after the close of trading on March 20. Allergan is in the process of being purchased by Actavis.
Last week, Skyworks Solutions replaced PetSmart in the index on BC Partner's acquisition of the pet supplies retailer.
In Europe, stocks closed mixed as investors awaited the outcome of the Fed's meeting. The FTSE rallied on an increased economic growth forecast of 2.3 percent for the United Kingdom, as finance minister George Osborne also signaled plans to scale back austerity measures—just in time for May's national election.
In the software market:
Oracle—The business software maker reported in-line quarterly profit of an adjusted 68 cents per share, although revenue fell below Street estimates. Oracle also raised its quarterly dividend by 25 percent to 15 cents per share.
Adobe Systems—The software firm reported an adjusted quarterly profit of 44 cents per share, beating estimates by 5 cents, while revenue was slightly above forecasts. Adobe did see a less-than-expected increase in subscribers to its Adobe Cloud service, although that was still 28 percent above a year ago.
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Microsoft—A blog post by Microsoft EVP Terry Myerson said Windows 10 will be available to consumers "this summer."
The Dow Jones Industrial Average closed up 227.11 points, or 1.27 percent, at 18,076.19, with Caterpillar leading gains and Wal-Mart the only decliner.
The S&P 500 closed up 25.14 points, or 1.21 percent, at 2,099.42, with energy leading all 10 sectors higher.
The Nasdaq closed up 45.39 points, or 0.92 percent, at 4,982.83.
Five shares advanced for every decliner on the New York Stock Exchange, with an exchange volume of 807 million and a composite volume of 4 billion in the close.
High-frequency trading accounted for 47.5 percent of daily trading volume, according to TABB Group. During the peak levels of high-frequency trading in 2009, about 61 percent of 9.8 billion of average daily shares traded were executed by high-frequency traders.
U.S. stocks closed mostly lower on Tuesday as investors focused on the outcome of the Fed meeting. The Dow was off triple digits and only the Nasdaq was in the black.
As of Tuesday's close:
- The Dow Jones industrial average was within half a standard deviation above its 50-day moving average. Since 1981 the index has been in this position 4.66 percent of all trading days, according to quantitative analytics tool Kensho. The probability of the index moving lower is 46.6 percent and the probability of it moving higher in the days following is 53.4 percent.
- The S&P 500 was within half a standard deviation above its 50-day moving average. Since 1980 the index has been in this position 5.23 percent of all trading days, according to Kensho. The probability of the index moving higher in the days following is 51.3 percent and the probability of it moving lower is 48.7 percent.
- The Nasdaq composite was within 1.5 standard deviations above its 50-day moving average. Since 1980 the index has been in this position 7.41 percent of all trading days, according to Kensho. The probability of the index moving lower is 61.9 percent and the probability of it moving higher is 38.1 percent.
—CNBC.com ontributed to this report.
Disclosure: CNBC's parent NBCUniversal is a minority investor in Kensho.