CNN  — 

The Trump administration’s tariffs on imported cars and auto parts will cost General Motors between $4 billion and $5 billion this year, as the nation’s largest automaker slashed its earnings projections.

CEO Mary Barra shared the estimates in a letter to shareholders released early Thursday. The letter, and earnings guidance for the year, were delayed from their planned release on Tuesday, when the company reported lower first-quarter earnings and awaited tariff changes from the Trump administration.

GM is the first major company to estimate, in dollars, how much President Donald Trump’s sweeping tariffs will cost it. Many others have walked back earnings forecasts because of the ensuing economic uncertainty.

Trump’s tariffs have unnerved not only global companies, but investors, nations and everyday Americans alike. Major stock indexes closed out a volatile April, and on Wedneday new data showed that the US gross domestic product unexpectedly shrank in the first three months of the year as recession fears abound.

The auto industry has been a particularly central target for Trump’s tariff efforts, with levies already in place on most imported automobiles and tariffs coming this Saturday on many of the imported parts used to build cars at American factories.

While GM is not the dominant global auto player it once was, it is still the largest American automaker, with US sales of 2.7 million cars and trucks last year.

It also has been very profitable, posting record net income of nearly $12 billion in 2024, excluding special items. Barra’s letter says that 1 million US workers depend on GM, either as employees, suppliers or dealers, with 50 US manufacturing plants and parts facilities in 19 states.

But Barra’s letter says the company now expects adjusted earnings before interest and taxes of between $10 billion and $12.5 billion this year, sharply lower than the $14.9 billion it earned on that basis last year, and less than the guidance it gave in January before Trump announced his levies.

GM faces tariffs on several fronts. It builds cars and trucks in Mexico and Canada, producing nearly 1 million vehicles in those two countries last year, according to S&P Global Mobility. Most of those vehicles end up being exported to US dealerships.

In addition, GM imported more than 400,000 vehicles from South Korea last year. All imported cars now face a 25% tariff, although the Canadian and Mexican tariffs can be reduced by credits for American- and Canadian-made parts.

In addition, all the 1.7 million cars and trucks GM built in the US last year depended on imported parts to some degree. According to an estimate from American University Kogod School of Business, GM’s US-built vehicles have American parts making up an average of 54% of their content.

Starting this Saturday, GM could face 25% tariffs on many of those imported components. While the Trump administration announced some partial offsets, GM could still face substantial costs.

Nevertheless, Barra thanked the Trump administration for the break on auto parts tariffs and raised hopes for further changes.

“We look forward to maintaining our strong dialogue with the administration on trade and other policies as they continue to evolve,” she said. “As you know, there are ongoing discussions with key trade partners that may also have an impact.”