* Facebook jumps after quarterly results beat expectations
* Twitter falls on weaker-than-expected user growth
* Verizon up after posting subscriber growth
* Durable goods order for June rises
* Indexes up: Dow 0.30 pct, S&P 0.12 pct, Nasdaq 0.37 pct (Updates to open)
By Tanya Agrawal
July 27 (Reuters) - U.S. stocks added to their record levels at the open on Thursday, driven by gains in Facebook and Verizon.
Facebook jumped 4.23 percent, lifting both the S&P 500 and the Nasdaq Composite indexes, after the social network's results beat Wall Street estimates.
Verizon surged 6 percent to $47 after its quarterly subscriber additions topped estimates. The stock was the second-biggest gainer on both the S&P and the Dow.
Earnings of S&P 500 companies are now expected to have climbed 9.9 percent in the second quarter, up from a projection of an 8 percent rise at the start of the month, according to Thomson Reuters I/B/E/S.
With equity markets at record levels, investors have been counting on strong earnings to justify the relatively expensive stock valuations.
"The earnings season has arguably taken on additional importance this quarter due to the inability of Donald Trump to, so far, deliver on the growth agenda that won him the White House back in November," said Craig Erlam, senior market analyst at online forex broker Oanda.
"Even in the absence of tax cuts and fiscal stimulus, corporate America has continued to perform well, with companies exceeding expectations on both the top and bottom line."
Investor sentiment also got a boost after the Federal Reserve left interest rates unchanged on Wednesday.
The central bank noted that both overall inflation and a measure of underlying price gains had declined.
The statement was perceived as dovish by investors, with rate futures pricing in a 38 percent chance of an interest rate hike by December, compared with a little over 50 percent chance priced in before the meeting.
At 9:43 a.m. ET (1343 GMT), the Dow Jones Industrial Average was up 64.76 points, or 0.3 percent, at 21,775.77 and the S&P 500 was up 3.18 points, or 0.12 percent, at 2,481.01.
The Nasdaq Composite was up 23.83 points, or 0.37 percent, at 6,446.57.
Five of the 11 major S&P sectors were higher, with the telecommunication index's 2.39 percent rise leading the advancers.
Twitter was down 13.46 percent after the company's quarterly results showed it failed to add users on a monthly basis in the second quarter, compared with the first quarter.
PayPal Holdings rose 2.53 percent, while Dunkin' Brands was up 2.60 percent after their quarterly reports.
United Parcel Service fell 2.25 percent despite the U.S. domestic package service posting a better-than-expected quarterly profit.
Online giant Amazon, Intel, Starbucks and Mattel are among those reporting results after the bell.
Economic data showed durable goods orders rose more than-expected in June, while weekly jobless claims rebounded from a three-month low last week.
Advancing issues outnumbered decliners on the NYSE by 1,263 to 1,249. On the Nasdaq, 1,177 issues rose and 1,154 fell. (Reporting by Tanya Agrawal in Bengaluru; Editing by Anil D'Silva)