Eight out of 11 sectors rose, with the S&P 500 communication services index, recently renamed and reconstituted with Facebook, Google-parent Alphabet and other internet and media stocks, jumping 0.80 percent.
Alphabet rose 1.20 percent and Facebook climbed 1.13 percent, both helping lift the S&P 500.
Apple rose 2.05 percent after JPMorgan started coverage of the stock with an "overweight" rating, citing the iPhone maker's quicker-than-expected move to a services business.
While raising interest rates on Wednesday, the Fed left its monetary policy outlook for the coming years largely unchanged. Stocks closed lower after the rate hike, but on Thursday some investors refocused on the central bank's confidence in the economy's growth.
"The Fed's statement is essentially a green light for the economy. It's a confirmation that the U.S. economy is the best game in town for global investors," said Jeffrey Kravetz, regional investment director at the Private Client Reserve of U.S. Bank.
Adding to feel-good sentiment was data showing economic growth accelerated in the second quarter at its fastest pace in nearly four years as previously estimated.
Amazon.com gained 1.93 percent after upbeat comments from brokerage Stifel about the company's retail, cloud, and advertising businesses. The online retailer opened a brick-and-mortar store in New York City on Thursday.
Starting on Monday, the telecommunications sector was renamed "communication services" and reconstituted with major internet and media companies alongside AT&T and other telecoms. So far this week, the S&P 500 communication services index has gained 1.5 percent, more than any other sector index.
The Dow Jones Industrial Average rose 0.21 percent to end at 26,439.93 points, while the S&P 500 gained 0.28 percent to 2,914.
The Nasdaq Composite added 0.65 percent to 8,041.97.
The S&P 500 materials index dipped 0.97 percent, while the utilities index added 0.96 percent, more than any other.
Accenture fell 1.69 percent after the consulting and outsourcing services company's full-year profit fell short of analysts' estimates.
Cruise operator Carnival Corp tumbled 4.84 percent after its fourth-quarter forecast missed estimates.
Conagra Brands slumped 8.54 percent after the packaged food company posted quarterly revenue that missed analysts' estimates.
That weighed on rivals, with Kellogg, JM Smucker and Campbell Soup shedding more than 2 percent.
Advancing issues outnumbered declining ones on the NYSE by a 1.22-to-1 ratio; on Nasdaq, a 1.01-to-1 ratio favored advancers.
The S&P 500 posted 17 new 52-week highs and 11 new lows; the Nasdaq Composite recorded 55 new highs and 63 new lows.
Volume on U.S. exchanges was 6.2 billion shares, compared to a 6.8 billion average over the last 20 trading days.
(Reporting by Noel Randewich in San Francisco, additional reporting by Amy Caren Daniel in Bengaluru; Editing by Nick Zieminski and Bill Berkrot)
By Noel Randewich
