BUI MAI PHUONG is an avid online shopper, ordering anything from clothing to personal care products from her smartphone. But she prefers to pay with cash.

She is among hundreds of millions of people whom firms such as Softbank Group-backed Grab and China’s Tencent want to win over as they try to tap into Southeast Asia’s burgeoning Internet sector.

More than 70 percent of the region’s 600 million-plus people do not use banks — higher than the global average of about 30 percent — and e-commerce is projected to hit US$88 billion by 2025.

But convincing consumers like Phuong, who lives in Hanoi, could be tricky.

“I have never tried using mobile payments because I don’t know how to use it and it seems a bit complicated to use,” said Phuong, 36, a manager at a construction material supplier in Vietnam.

Mobile payments are ubiquitous in China; a consumer can spend a day without using cash at all in Beijing or Shanghai. But cash remains king in Southeast Asia.

Hard currency, paid on delivery, accounted for 44 percent of total e-commerce transactions last year and is likely to remain the most popular payment option for at least the next three years, according to data by research firm IDC.

“The biggest challenge for users and merchants to adopt cashless is the fact that cash remains ubiquitous, easy to use and inexpensive,” said ride-hailing firm Grab, which has ventured into e-wallets.

And the mobile payment marketplace in Southeast Asia remains wide open, with no dominant players.

Indonesia’s ride-hailing firm Go-Jek’s Go-Pay, Singapore-based Grab’s GrabPay, Japan’s messaging app Line’s Line Pay, Momo e-wallet owner M_Service in Vietnam and Voyager Innovations, which operates Paymaya in the Philippines, have all entered the fray. The gaming company Razer Inc. has also indicated it is eager to play a role.

Cash on delivery costs e-commerce businesses more than other payment methods, said Alibaba Group Holding-backed e-retailer Lazada Group.

For example, sometimes a customer does not have enough cash on hand, or is not home to pay for the delivery. In those cases, the product must be sent back to the seller, adding logistical costs, Lazada said.

Mobile payment companies bet they can transform their platforms into financial supermarkets, offering everything from loans to insurance on top of payment options.

At the moment, usage is spotty. E-wallets will account for 16 percent of total e-commerce transactions in Southeast Asia by 2021, up from last year’s 9 percent, according to IDC.(SD-Agencies)