Stocks extended losses in afternoon trade on Friday, after holding closer to the flatline earlier in the day.
"I think it's a quiet day in markets today, the GDP a slight disappointment, and (the) market's responding appropriately," said Jack Ablin, chief investment officer at BMO Private Bank.
Shares of Coca-Cola, which took a 16.7 percent stake in Monster Beverage last year, traded more than 2 percent higher. Monster reported after the bell on Thursday that it earned 72 cents per share for its latest quarter, 13 cents above estimates, while sales were also well above estimates. The company's results were helped by a jump in overseas sales.
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Crude oil futures settled up 3.3 percent, to 49.76 a barrel, for the first monthly gain since June. Brent edged above $62 a a barrel.
Futures were little moved after the second reading on the U.S. fourth-quarter gross domestic product showed slower growth than the initial report on the quarter.
Fourth-quarter GDP was revised to show growth of 2.2 percent. Analysts polled by Reuters expect GDP growth of 2.1 percent, after a final reading of 5.0 percent in the third quarter.
"We're two-thirds done with the first quarter," said Peter Boockvar, chief market analyst at The Lindsey Group. "The fourth quarter is old news. (GDP) should have no relevance on today's market."
Tim Hopper, chief economist at TIAA-CREF, noted that the significant downward revision in inventories accounted for most of the pullback from the first reading of 2.6 percent.
"Ironically I think it's a good sign for growth in the first quarter," he said. "We have fewer inventories to work off before we start spending again."
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The Chicago Purchasing Managers Index came in at 45.8, the lowest since July 2009. Boockvar partly attributed the contraction level, not seen since April 2013, to the West Coast port strike.
"Now that the strike is over, things will of course normalize but will take a few months to do so," he said in a note. "Whether there is weakness notwithstanding the port strike remains to be seen but we have seen a variety of lackluster economic data points that have mostly missed consensus estimates."
Consumer sentiment came in at 95.4 for February, beating expectations but down from January's 98.1.
Pending home sales were the highest in 18 months, the National Association of Realtors said.
"Neither (sentiment) or the home sale one should have any market impact today," Boockvar said in a note. "European Central Bank quantitative easing and whether 'patient' comes out of the mid March Federal Open Market Committee's statement are the sole focus over coming weeks."
Investors will also be watching a raft of officials from the U.S. Federal Reserve speaking today.
Stanley Fischer, vice chair of the Federal Reserve's board of governors and voting member on the Fed's policymaking committee, told CNBC Friday afternoon that there is a "high probability" of a rate increase this year.
Earlier Friday at the University of Chicago's annual U.S. Monetary Policy Forum in New York City, Fischer said that the Fed's balance sheet size could present a challenge to raising rates, but he still said the FOMC expects to raise rates in 2015.
The Federal Reserve may have to get even more aggressive with policy if its efforts to tighten aren't reflected in short-term interest rates, New York Fed President Bill Dudley said at the conference.
Cleveland Federal Reserve Bank president Loretta Mester said at the same conference that there were risks to holding interest rates lower for too much longer, including potential financial stability concerns and an erosion of public confidence in the economy.
The Dow Jones Industrial Average closed down 82 points, or 0.45 percent, at 18,132.38, with American Express the greatest laggard and Coca-Cola the greatest of seven blue chip advancers. The Dow gained 5.64 percent for the month, its best since January 2013.
The S&P 500 closed down 6.24 points, or 0.30 percent, at 2,104.49, with information technology the greatest decliner and consumer staples and telecommunications the only two advancing sectors. The S&P was up 5.49 for the month, the best since October 2011.
The Nasdaq closed down 24.3 points, or 0.49 percent, at 4,963.53. The index gained 7.08 percent for the month, its best since January 2012.
The CBOE Volatility Index (VIX), widely considered the best gauge of fear in the market, traded below 14.
Advancers were a step ahead of decliners on the New York Stock Exchange, with an exchange volume of 738 million and a composite volume of 3.3 billion in the close.
High-frequency trading accounted for 47.5 percent of February's average daily trading volume of 6.8 billion shares, 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