Instead, the ride-sharing service typically bills a customer’s credit or debit card through its smartphone app. The idea is that riders can hop in and out of cars and be billed automatically for their trip, without fishing through their wallet to pay a driver.

Now Uber’s starting to change that system. The company’s going old-school with a brand-new feature for some of its riders in Singapore: the option to pay with cash. How retro.

On Wednesday Uber announced the so-called “experiment” with cash payments in Singapore, which is a first for riders in the developed world. The company says the move could pave the way for more cash payments in other major cities too.

Uber already lets some riders pay with cash in more low-income countries like India, Malaysia, and the Philippines where cards aren’t yet ubiquitous.

But in Singapore, plastic rules. Singaporeans have on average two debit cards apiece and at least one credit card, Reuters reports. Being stuck with cash as an only option in the country isn’t a likely scenario.

Still, Uber’s betting that giving customers more ways to pay will help the company pick up more new riders:

“Cash opens doors for more Singaporeans to take their first ride, and have a quality experience on Uber, whether you’re busy Mum, a student without a credit card or a senior citizen who’s more comfortable with cash,” Uber said in a release.

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If the cash model proves successful in Singapore, Uber might move the option to other well-developed Uber-riding cities. Uber Singapore general manager Warren Tseng says “whatever we learn here you could see later in cities like New York, London,” Mashable reports.

3 Questions With Uber’s Ryan Graves:

So maybe cash isn’t king anymore in the developed world, but it’s just one more way Uber, the company valued at over $60 billion, is battling to get more and more of the globe’s customers on board.