"Our economists expect that a deal will eventually be struck that leads to a "staggered off-ramp" for existing tariffs, but believe that the likelihood of a final round of tariffs on the remaining $300 billion of imports has risen to 30%," David Kostin, Goldman's chief U.S. equity strategist, said in a note to clients over the weekend. "Tariffs pose a greater risk to company profit margins than to sales."

Goldman Sachs estimates that if the president imposes duties on the remaining $300 billion in goods not already targeted, it could lower earnings estimates for U.S. companies by up to 6%.

Should President Donald Trump follow through on threats to put tariffs on virtually all Chinese imports, it could have a significant impact on the bottom line for American companies.

That impact is in a worst-case scenario, issued as the U.S. escalated tensions in the trade war by raising the tariff level to 25% from 10% on $200 billion worth of goods.

In reality, Goldman said the impact probably will be less as companies adjust prices to make up for increased costs that the tariffs generate. The firm expects that companies in aggregate will have to increase consumer prices by 1% to make up for the tariff costs.

Impacts, though, vary by companies. The semiconductor industry, which counts on China for supplies, takes probably the biggest hit, and that has shown up in stock prices.

Shares of S&P 500 semiconductor companies have tumbled more than 13% in the past month as angst has intensified over how long it will take the U.S. and China to reach an agreement. The sector is easily the worst performer on the large-cap index, followed by autos, which are down 6.5% on fears that the industry also could get hit by tariffs.

Corporate earnings are coming off a sluggish quarter. With 92% of S&P 500 reporting, companies have seen an overall 0.5% profit decline, the first negative reporting period since the second quarter of 2016, according to FactSet.

Goldman noted signs of margin pressure, even though earnings actually turned out better than analysts had expected. Even with the trade tensions, earnings estimates have improved, with the firm now projecting a full-year earnings per share gain of 3%, pushed by tax benefits and rising oil prices.

"Despite these tailwinds, broad-based positive 2019 EPS revisions will likely require a pickup in economic growth or improved pricing," Kostin wrote.