Apple, the most heavily traded stock of the day, gained 2.6% to $97.19 after reporting third-quarter profit up 12% from a year earlier and revenue 6% higher to $37.4 million.
PepsiCo shares popped 1.9% to $90.82 after the beverage and snacks giant booked stronger-than-forecast earnings and raised its full-year profit outlook.
Microsoft on Tuesday evening reported fiscal fourth-quarter earnings of 55 cents a share, 6 cents less than analysts' estimates, and revenue up 17.3% to $23.38 billion. Microsoft shares ended the session slightly higher, up 0.09% to $44.87.
Delta Air Lines (DAL) added 3.9% to $39.15 after reporting quarterly net income 17% higher to $801 million as passenger revenue increased 9.1% to $9.27 billion.
So far, 149 companies in the S&P 500 have reported earnings with 68.5% beating analysts' expectations.
The S&P 500 climbed by 0.18% to 1,987.01, skimming record highs set earlier in the day. The Nasdaq gained 0.4% to 4,473.70. The Dow Jones Industrial Average ticked 0.16% lower to 17,086.63.
U.S. stocks moved back into record-making territory on Tuesday as positive earnings overshadowed continued unease in Eastern Europe and the Middle East. Boosting the index, Chipotle (CMG), Comcast (CMCSA) and Verizon (VZ) gained following better-than-expected earnings reports.
S&P Capital IQ reported that S&P 500 second-quarter earnings growth is now expected to come in at 7% year over year, with earnings per share of $28.80. All 10 sectors are anticipated to have grown the second quarter.
Meanwhile, a report from Yardeni Research said that S&P 500 forward earnings rose to a record high last week and have risen in 23 of the past 24 weeks.
Aerospace giant Boeing (BA) hiked its 2014 earnings per share outlook to between $7.90 and $8.10 from its previous forecast of $7.15 to $7.35. Net earnings for the second quarter increased by 52% to $1.65 billion as its backlog remained strong at $440 billion with more than 5,200 commercial airplane orders. The stock dragged on the Dow as it slipped 2.3% to $126.71.
Facebook (FB) is up 0.8% to $71.73 after the bell. The social network reported second-quarter earnings of 42 cents a share, 10 cents higher than analysts' estimates.
AT&T (T) is slipping 0.78% to $35.60 in extended trading after earnings of 62 cents a share missed expectations by a penny.
Herbalife (HLF) was also drawing attention. Activist investor Bill Ackman denounced the weight loss and nutritional supplements company as a pyramid scheme in a three-hour presentation on Tuesday, but Wall Street shrugged off his criticism and sent the company's stock soaring more than 25% over the day's session. Shares pulled back on Wednesday, dropping 2.5% to $66.11.
-- By Andrea Tse and Keris Alison Lahiff in New York.