Investors had high hopes for this earnings season, with S&P Capital IQ's earnings growth forecast at 6.2 percent entering the season.
Earnings have been a tailwind for stocks recently, as the major U.S. stock indexes notched record highs.
"The SPX saw upside follow-through last week, making progress toward the measured move projection of 2507 derived from its latest breakout," Katie Stockton, chief technical analyst at BTIG, said in a note.
Wall Street also got ready for the latest monetary policy announcement from the Federal Reserve. The central bank is largely expected to keep interest rates unchanged, having hiked in their previous meeting.
Market expectations for a rate hike were just 3.1 percent Monday, according to the CME Group's FedWatch tool.
"The Fed is dragging its feet as rate hikes trail inflation's trajectory. The problem is inflation trends are negative," said Jack Ablin, chief investment officer at BMO Private Bank, in a note. "Loan demand is easing while loan standards are tightening. Lower monetary velocity dampens the inflationary effect of money printing."
Investors also kept an eye on oil prices as officials from OPEC and non-OPEC countries met in Russia to discuss compliance of agreed production cuts and how to bring down inventory levels.
U.S. crude futures for September delivery rose 1.3 percent to settle at $46.34 a barrel.
In economic news, the IHS Markit Flash US Composite PMI hit its highest level in six months. IHS said in a release the growth in business activity was driven by "by a steeper increase in manufacturing production in July."
Existing home sales fell 1.8 percent to a seasonally adjusted annual rate of 5.52 million units last month, more than expected.