Almost a third of people in Ireland say they are using the internet "all the time" or "nearly all the time" while in lockdown.
New CSO figures show 13% of people ordered food or drink online in March, which is more than double the amount recorded in January.
Internet users are also ordering more cleaning products, furniture, and gardening items online.
However, the number of people buying the likes of cinema and concert tickets over the internet dropped by 16% from January to March.
"People are at home a lot more now, with schools and many workplaces closed. This has had an effect on people’s use of the internet during this time," explained CSO statistician Maureen Delamere.
"The changes have impacted in the way people are doing their shopping and what they are buying," she added. "Clothes and sports goods which were usually the most popular online purchase, have decreased in March while the purchase of food or drink from shops or meal-kit providers has more than doubled from 6% in January to 13% of internet users in March."
There have also been increases in people using email, video-call services such as Skype or Zoom, as well as people looking up health information online.