This year was supposed to be a banner moment for digital commerce companies.

Klarna, the digital payments giant, was gearing up for an initial public offering. So was Chime, the financial services company. And StubHub, the online ticketing business, had spoken to bankers for months about pursuing an I.P.O.

But after President Trump unveiled a barrage of tariffs this week, companies across the industry scrambled to deal with the fallout.

Among other moves, Klarna, Chime and StubHub all paused their I.P.O. plans, aiming to wait out the market volatility, people with knowledge of the matter said. And companies that provide online sellers with payment processing services, like Shopify, are lobbying for changes to Mr. Trump’s tariff policies and advising customers on how to weather potential economic difficulties. Stripe, a payments start-up, and Block, a payments and money transfer services company formerly known as Square, are making similar moves.

It might seem counterintuitive for tariffs to bring pain to digital commerce companies, which sell goods or provide services online. But these businesses are set to be affected in roundabout ways.

Retailers like Amazon, which act as clearinghouses for online merchants, could feel the effects if fewer people buy foreign exports on their platforms. And companies like Klarna profit from fees they charge small businesses for processing digital payments, which could be in serious jeopardy if people buy fewer items online.

“If this game of chicken continues through 2025 and even longer, this is going to be very painful for the entire retail industry,” said Sucharita Kodali, an analyst for Forrester who covers retail and e-commerce. “It’s going to be bad for everyone.”

On Wednesday, Mr. Trump said the tariffs would reverse decades of what he called unfair treatment by the rest of the world and bring factories and jobs back to the United States. “The markets are going to boom,” and “the country is going to boom,” he said.

But with the tariffs being far broader and more severe than expected, many tech companies immediately began feeling the pain. Apple, Oracle and Dell — which have global supply chains that are likely to be disrupted by the tariffs — were the most obvious candidates to face fallout.

Digital-first companies that deal in online sales could lose just as much. Meta and Google, for instance, were pressured by the threat that businesses, especially Chinese companies, would pull back on buying e-commerce ads on their platforms.

The biggest e-commerce company, Amazon, which has millions of third-party sellers that ship goods from China — one of the countries hardest hit by Mr. Trump’s tariffs — saw its shares slide more than 9 percent since the tariffs announcement.

John Blackledge, an analyst at TD Cowen, lowered estimates for Amazon’s revenue, operating income and earnings per share by 3 percent to 4 percent between 2026 through 2030, specifically because of how Mr. Trump’s “worse than expected” tariffs would hurt the company’s marketplace, according to a research note on Thursday.

Some digital commerce firms may weather the disruption. StubHub, which sells tickets to live events, bounced back after downturns during the Covid pandemic and the 2008 financial crisis. And customers of Chime, which offers digital services like a mobile banking app and checking accounts, tend to use its products for buying items like gasoline and groceries, which are typically less sensitive to economic swings.

But Shopify, Klarna and Stripe are all vulnerable to Mr. Trump’s tariffs. Payment processing platforms like Stripe tend to trend with the global economy and the strength of online shopping. If small businesses increase prices because of tariffs, consumers are likely to buy fewer products online. And because these companies get most of their revenues from fees for processing merchant sales, a dip in sales volume could affect all of their businesses.

Klarna, StubHub, Chime and Stripe declined to comment. Details of Klarna’s, StubHub’s and Chime’s I.P.O. plans were reported earlier by The Wall Street Journal and Axios.

A Shopify spokeswoman pointed to recent blog posts advising sellers on how to navigate a choppy environment if tariffs hamper their businesses.

“Without small-business protections, legitimate entrepreneurs suffer under policies intended to curb exploitation,” the company said in a blog post. “This hikes costs, disrupts supply chains, and hinders cross-border trade.”

The company said it supported Mr. Trump’s addressing some loopholes in the tariff system, including the “de minimis exemption,” which exempted businesses from paying tariffs on exports to the United States valued at under $800.

But it cautioned against policies that went too far. “Addressing this abuse is justified, but small businesses can’t become collateral damage,” Shopify said.

Michael J. de la Merced contributed reporting.