U.S. stock markets were expected to open lower on Wednesday in the wake of disappointing earnings from tech heavyweights.
Existing home sales data for June are due out at 10 a.m. ET, although economic data may play second fiddle to earnings season for now.
Apple's shares tumbled almost 7 percent in after-hours trade on Tuesday after the firm's fourth-quarter revenue forecast fell short of forecasts and it missed some targets for iPhone sales.
Microsoft shares, meanwhile, fell more than 3 percent in late trading after posting a $3.2 billion net loss for its fiscal fourth quarter ending June 30 following restructuring charges.
The slide in tech stocks set the tone for trade in global equity markets: Asian stocks closed mostly lower, while Europe's main bourses were all in the red in early trade.
U.S. stock futures traded broadly lower, with benchmark Dow Jones industrial average futures trading about 70 points lower after trimming earlier losses.