Experts: Online sales to top $500B by 2020

Online sales are expected to reach $300 billion in 2014, $335 billion in 2015 and $512 billion by 2020.

According to business forecasting experts at FTI Consulting Inc., online sales will continue to grow at a double-digit rate for the next several years.

FTI Consulting reports that the online channel's share of total retail sales (excluding autos and gasoline) is now approaching 11%, compared with 7.4% in 2010. The online channel also accounts for approximately 15% of general merchandise, apparel and accessories, furniture and other sales category spending during the holiday season.

FTI Consulting reports that nearly three-quarters of the growth in sales will accrue to the online channel, as it is led by the growth in mobile devices.

In addition, the spillover of spending from holiday gift card redemption continues to make January the strongest month for online shopping relative to total monthly retail sales.

The 2014 Holiday Retail Forecast predicts a 3.5% increase in nominal holiday sales this season.