Growth is predicted by IGD across all major grocery channels, including supermarkets and hypermarkets, online, convenience and discounters.
Joanne Denney-Finch, IGD chief executive, said: “There’s a revolution underway in food and grocery, in terms of what, how and where shoppers do their shopping.
“On average, shoppers say they use around 12 different stores every month - and in the future, we will have an even greater choice in what, where and how we buy our food.”
The forecast showed that while online is to remain the fastest growing channel, forecast to grow 53.8%, it might not grow at the same pace as previous years.
Denny says that 24% of British shoppers will, in the next two or three years, be likely to use online subscription services to get their groceries delivered.
She said: “So the pace of change will be rapid - and this will present huge challenges and opportunities for the industry.”