One in four consumers now shops for groceries online, according to a new survey by Mintel.

The study by retail analyst Mintel suggested online grocery sales were worth £8.6bn last year, and it is predicting they will soar 73% by 2020, to reach £15bn.

Last month, supermarket giant Morrisons announced a new supply deal with American online retailer Amazon.

The survey also said that British consumers have embraced internet shopping faster than any other nation in the world, and average online spending per head is greater than any other nation, including America.

It said 43% of shoppers are doing some of their grocery shopping, typically heavy things like tins, washing powder and nappies, online.

Almost one in four people said they are already doing most or all of their food and cleaning product purchases on the web.

One in five of young adults aged 25-34 is now doing all of their grocery shopping online.

Mintel said: “The days of heading to the supermarket are over for some Brits, as they trade trolleys for home delivery.”

Convenience a factor

It added: “The main reason consumers cite for shopping online more is convenience, with 60% of Brits who are shopping more online doing so because it is more convenient than visiting stores.”

The news comes as Tesco launched its own automatic ordering system for online purchases. The supermarket’s new system lets users set automatic orders of items for specific days.

For example, shoppers can request a recurring order for bread on a particular day of the week. The new ordering tool also lets users set up price alerts that will automatically order an item if it goes down in price.