Online commerce will represent almost one-fifth of all retail sales in Mexico by 2018, forecasts the consultancy Euromonitor International. The increase will be the result of increased Internet availability and growth in the number of smartphones and tablets, as well as increased practicality.

Sales by Internet and by telephone will grow 12 percent in the next five years and will represent 19 percent of the revenues of commercial chain stores. In 2013 that figure was 7 percent.

The number of Mexicans connected is expected to rise from the current 41 percent to 52 percent in four years, said Euromonitor analyst Ingrid Belmont.

Walmart launched its online store in 2013 and reported more than 28 million visits after seven months of operation. Its other portal, Superama, recorded 7.5 million users last year on its website and through its mobile applications.

The company has said it will launch the site sams.com.mx this year.

Walmart has a distribution center exclusively for the delivery of merchandise purchased online. Home delivery is available in 48 cities.

Francisco Guzmán, an analyst with the financial services firm Grupo Financiero Interacciones, believes that Walmart intends to be the Amazon of electronic commerce in Mexico. Guzmán thinks this will prompt other chains to do the same.

There are already several other players in e-commerce in Mexico. Soriana, for one, reports double-digit growth in sales so far this year. Other stores offering online sales are Costco, Palacio de Hierro, Liverpool, Amazon, Dafiniti, Linio, and Modalia.

Electronic commerce was valued last year at 121.6 billion pesos, with the bulk of sales being in music and films, says the Mexican Internet Association, noting that 37 percent of Internet surfers spend between $400 and $1,000 pesos each time they buy online.

To encourage sales, online stores offer alternatives to paying with a credit card, such as bank deposits, PayPal, or cash on delivery.