"No change in Fed rate target and little indication of a commitment to increasing rates still this year is driving dollar down and providing support to gold," said Rob Haworth, senior investment strategist for U.S. Bank Wealth management.
"Fed comments about global market volatility and global economic risks are also supporting, likely, safe-haven flows into gold."
Haworth said, however, that the surge is likely short-lived as demand for physical gold appears soft and "ultimately we will be faced with a similar debate as we get to the October meeting."
U.S. gold futures for December delivery settled down 0.2 percent at $1,117 an ounce, before the Fed statement.
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Expectations ahead of the statement were mixed, with a Reuters poll showing 45 out of 80 economists expected the Fed would keep its benchmark interest rate between zero and 0.25 percent.
Uncertainty over the Fed's decision kept gold in a narrow range early this week, but on Wednesday the metal saw its biggest rally in four weeks after data showing the surprise dip in U.S. inflation last month.
Signs of a disinflationary trend in the United States contrast with a fairly healthy economy and falling unemployment rate, and highlight the dilemma Fed officials face as they contemplate raising rates this year.
Silver was up 1.8 percent at $15.16 following a 3.5 percent jump in the previous session. Platinum was up 0.7 percent at $974.74 an ounce and palladium was up 0.1 percent at $609.50.