Atlas DMT anonymously analyzed holiday shopping behavior across 28 companies. Mondays are the busiest online shopping day, according to Atlas DMT. The finding points to the fact that consumers shop in physical store locations during the weekend, then jump online on Mondays to comparison shop. The Atlas study reports that Fridays, typically slow days for online shopping, are stronger than usual during the holidays. Weekdays between noon and 3 pm EST, are the most active online shopping days during the holidays.