U.S. stocks were down slightly at the opening bell on Monday, putting the S&P 500 on track to snap a 4-day winning streak after data showed Americans only modestly increased spending and Spain slipped into recession.
U.S. household income rose in March by the most in three months but consumers only slightly increased spending instead saving more, Commerce Department data showed.
"This is decent overall but nothing amazing. The spending number is an indication that the higher gas prices we saw last month are taking their toll," said Todd Schoenberger, managing principal at the Blackbay Group in New York.
The S&P 500 is down 0.4 percent for April, putting the index on track for its first monthly decline since November as investors grappled with a flare-up of the euro zone debt crisis and U.S. data that has hinted at a stalled recovery.
Moments after the closing bell, the S&P 500 fell 2.47 points. Dow Jones industrial average slipped 4.43 points, and the Nasdaq lost 6.82 points.
With deep government spending cuts to reduce a massive deficit and troubles in the banking sector likely to delay any return to growth, Spain's economy sank into recession in the first quarter.
Humana Inc dropped 4.4 percent to $83.98 in premarket trading after the company, one of the largest providers of Medicare plans for the elderly, posted a 21 percent decline in profit, missing Wall Street's target.
A total of 12 S&P 500 companies were scheduled to report earnings on Monday, including Anadarko Petroleum Corp and McKesson Corp .
According to Thomson Reuters data through Friday, of the 275 S&P 500 companies that have reported results, 72 percent topped estimates. A strong earnings season has helped lift the benchmark S&P index to its best week since mid-March on Friday.
Pipeline operator Energy Transfer Partners LP will buy Sunoco Inc for $5.3 billion as it focuses on transporting more crude oil and refined products amid falling natural gas prices. Sunoco soared 21.2 percent to $49.60 and Energy Transfer rose 2.6 percent to $49.15 in premarket trading.
Barnes & Noble Inc surged 91.5 percent to $26.20 premarket after Microsoft Corp said it will invest $300 million in the bookseller's digital and college operations in a deal that values the businesses at $1.7 billion.
Gen-Probe Inc climbed nearly 20 percent to $82.02 premarket after Hologic Inc said it would acquire the diagnostic test maker for about $3.75 billion in cash. Hologic shares dropped 3.9 percent to $20.40 premarket.
Reuters contributed to this report.