Wang Manni, 23, a graduate student in Hangzhou, is a loyal customer of one of the world’s biggest finance companies. However, it is not one of the traditional banking giants that handles her business, rather a four-year-old spin-off from the technology conglomerate Alibaba, Ant Financial. She uses its virtual credit cart, Huabei, to buy groceries, makeup and electronics on Taobao, Alibaba’s massive e-commerce business. Sometimes she puts her monthly allowance from her parents into Ant’s money market fund, Yu’e Bao, to earn a little interest to help repay her shopping debts.

“I often don’t know I’ve spent that much money until I see the bills at the end of the month,” she said.

It is because of people such as Wang, part of a $13tn mobile payments market, that Ant Financial is one of the world’s most valuable fintech companies.

The Hangzhou-based firm, controlled by the Alibaba founder and executive chairman, Jack Ma, is reportedly raising funds that would value it at $150bn. That would make Ant the world’s most valuable startup, larger than Goldman Sachs, Morgan Stanley and several Chinese banks.

The company occupies a grey area between an internet company, a bank and a payment platform, underlining the rise of Chinese tech companies and the regulations at home and abroad that are only just catching up to them

Ant Financial, established in 2014, grew out of Alipay, an escrow payments service started by Alibaba in 2004 to serve shoppers and merchants on Taobao. In 2011, Ma controversially carved out Alipay from Alibaba and took full control of the company. Ant’s last funding round, from Chinese investors in 2016, put a valuation of around $60bn on the company.

Today, it offers credit services such as Huabei, insurance products, micro-loans to online merchants and other small and medium-sized businesses, as well as investment products. Its credit scoring system, Sesame Credit, is one of the largest in the world. Yu’e Bao has $233bn under management as of last year, making it the world’s largest money market fund.

Analysts say it is the ubiquity of Ant in the daily lives of Chinese consumers that underpins its valuation. “It’s really hard to define what kind of company Ant Financial is,” Li Chengdong, an independent e-commerce analyst based in Beijing, said.

“You can think of Ant Financial as the water, electricity, and coal in your life. Ant Financial is everywhere in your life, from daily payments, to renting a house to renting a bicycle,” he said.

The company has pledged to have 2 billion users worldwide; at the moment it has 870 million, including those through its partners outside China, in India, Indonesia, Singapore, Thailand and elsewhere.

“The prize at the end is so large that investors are still running in”, Joe Ngai, managing partner of McKinsey’s Greater China practice, said. “This is essentially a digital wallet, which isn’t new but what is new in China is the fact that so many people are on it and that it’s at such scale.”

“If Facebook started a bank, that’s kind of what it feels like,” he said.

The company sees itself more as a “lifestyle platform” on which people such as Wang conduct most of their life’s transactions. From ordering food, buying movie tickets, to paying utility bills. “The idea is people are living their lives through this platform,” an Ant Financial spokesperson said.

Between January and October last year, Chinese shoppers spent $12.8tn on mobile payment platforms, dwarfing mobile payments in the US of an estimated $49.3bn, according to data from eMarketer, a market research firm.

Yet there is still room to grow. Of the country’s more than 720 million mobile phone users, only about a third use mobile payments, according to China’s Internet Network Information Centre.

Young Chinese such as Wang, part of China’s “post-90s” generation , are a particular force. Analysts call them “empowered” consumers who grew up with Taobao and Alipay and adopt new online products and services confidently and quickly.

Companies such as Alibaba and its rival Tencent are giving Chinese consumers and businesses new access to credit. China’s state-owned banks have traditionally focused on the country’s state-owned companies. In 2014, fewer than 10% of Chinese had access to credit through some sort of financial institution, according to the World Bank.

Analysts and investors expect Ant to go public within the next two years. The company declined to comment on any possible listing or reports on its valuation.

The company has not been without setbacks. US officials in January blocked its purchase of MoneyGram International, a cross-border payment system, for $1.2bn, out of national security concerns. Chinese regulators may have similar concerns: an IPO abroad, such as Alibaba’s in 2014, would give foreigners control over a critical Chinese payments system.

Chinese regulators have also been cracking down on online lenders and China’s fast-growing micro-credit market. Ant, which dominates the online credit market, repackages these consumer loans into asset-backed securities (ABS) to be sold on to investors. However, late last year regulators banned microlenders from raising funds via ABS.

Ant also faces more competition from Tencent, which owns China’s most used messaging app WeChat. Users can also conduct most of their financial transactions – paying bills, transferring money and investing on the app, known in China as Weixin.

Ant’s greatest advantage may be its trove of data on how people shop, how quickly they pay back their debts and hundreds of other transactions that are analysed to calculate a credit score.

Ant is likely to expand into other financial products and move into other emerging markets. The company said it is working on encouraging merchants in the US to accept Alipay to target Chinese tourists travelling there.

In China, Ant continues to ingratiate itself into people’s lives. The company has invested in food delivery services and bike-sharing companies. Users with high Sesame Credit can pass through customs faster or stay in hotels without having to put down hefty deposits as is usually required.

These perks and the ease of Ant’s products only make them more addictive. Wang, who relies on Ant’s Huabei credit for most of her purchases, is trying to cut back. “It’s not a question of whether or not to use it but whether I can control myself.”

Additional reporting by Wang Xueying