The latest $300 million investment more than doubled the two-year-old company's valuation from $1.6 billion in April and brought its total capital raised through a mix of debt and equity financing to $620 million.

The round included Redpoint Ventures, Thrive Capital, D1 Capital Partners, Spark Capital, fintech behemoth Stripe and several other investors.

Change in how consumers use financial services and a pandemic-driven rise in digital channels have drawn investor interest in fintechs in recent months, prompting global investors such as Sequoia Capital, Tiger Global and SoftBank Group Corp to ramp up bets on the sector.

Ramp offers virtual and physical cards and gives a 1.5% cashback on every purchase a customer makes, serving several high-profile companies such as audio app Clubhouse, telehealth company Ro and online legal services provider DoNotPay.

It makes money by taking a share of the interchange fee that is paid by the merchant every time a user spends through its card. The startup competes with American Express and other startups such as Brex and older expense management software makers including Expensify and SAP Concur.

Ramp on Tuesday also announced the purchase of Buyer, a "negotiation-as-a-service" platform that helps businesses cut down costs, marking its first acquisition. The deal's financial terms were not disclosed.

(Reporting by Niket Nishant in Bengaluru; Editing by Aditya Soni)