Klarna Bank AB is considering raising fresh funds at a significantly lower valuation than it achieved a year ago, according to people familiar with the situation, a sign of the punishing environment for tech companies.

The Swedish payments firm is in talks with investors about a deal that could value the company at around $15 billion, the people said, less than it was seeking just last month. The Wall Street Journal reported Klarna was in talks to raise up to $1 billion at a low $30-billion-range valuation. One of the people said the current talks could yield at least $500 million. There is no guarantee a deal will take place.

A $15 billion valuation would be a substantial comedown for Klarna, which became Europe’s most valuable financial-technology startup last June when SoftBank Group Corp.’s 9984, -4.24% Vision Fund 2 led an investment that valued the company at $45.6 billion. Other investors include Sequoia Capital, Silver Lake and Dragoneer Investment Group LLC.

Klarna specializes in buy-now-pay-later services, a popular type of cash advance that competes with credit cards. The services are offered to customers at the point of purchase, mostly online, and lets them pay for goods and services in installments without paying interest. Klarna makes money by charging a fee to merchants who offer Klarna’s services.

An expanded version of this story appears on WSJ.com.

Popular stories from WSJ.com: