Equity markets tend to flourish on the promise of extra central bank stimulus, because cutting rates or buying bonds pushes down yields, prompting investors to look for returns elsewhere.
The Dow Jones industrial average edged up 10.14 points, or 0.1 percent, to 18,516.55. Eastern time. The Standard & Poor's 500 index gained 2 points, or 0.1 percent, to 2,165. The Nasdaq LittComposite lost 0.09 percent to finish at 5,029.59.
"It was a bit of a reversion to the mean", said Chuck Self, chief investment officer of iSectors in Appleton, Wisconsin, on the rally in United States shares losing steam.
SUPPLEMENT SURGE: Herbalife rose $9.21, or almost 16 percent, to $68.57 after the supplements company agreed to pay $200 million to resolve allegations by the federal government that it deceived consumers. The deal puts an end to a Federal Trade Commission investigation of the nutritional supplements company that had stretched over two years.
Citigroup shares contributed to the rally, with a 0.6% gain after the bank reported better than expected second quarter results. That would be the fourth quarter in a row of falling profits, rare outside of a recession.
"The fact that the Bank of England chose to hold off the rate cuts suggests the Brexit is unwinding in an orderly manner", Karyn Cavanaugh, senior market strategist at Voya Financial, told MarketWatch.
J.P. Morgan kicks off the earnings season for US banks and sets the tone for the industry.
Bill Strazzullo, chief market strategist at Bell Curve Trading, expects stocks will continue to climb in future weeks, but he's anxious.
European equities, which also had big gains for the week, finished in indecisive fashion after a deadly attack in Nice, France, darkened sentiment. Britain's FTSE 100 was 0.1 percent lower.
Japanese game maker Nintendo jumped another 9.8 percent, its latest gain in the wake of the Pokemon Go phenomenon sweeping the planet.
In Asia, Japan's Nikkei 225 rose 0.7 percent. The three major indexes closed their third week of gains, a period in which the S&P has advanced more than 6 percent.
West Texas Intermediate (WTI) futures rose 8 cents or 0.2% to close at $45.76 a barrel on the New York Mercantile Exchange. Brent crude, a standard for worldwide oil prices, climbed 24 cents to $47.61 a barrel.
Excluding food and energy, inflation rose 2.3% year-on-year in June, compared to estimates for the consumer price index to remain unchanged at 2.2%. The yield on the 10-year Treasury note rose to 1.60 percent from 1.54 percent, a big move.
On the currency markets, the dollar was trading at $1.32 against the pound, while the euro was worth £0.83 pence sterling.