US companies are paying more than ever before in tariff duties: $6.2 billion in October. The October tariff collections represented a 104% jump from October 2017.

The sudden spike came because of President Donald Trump's tariffs on steel, aluminum, and Chinese goods.

US companies paid $2.2 billion more to import goods subject to Trump's tariffs in October.

The costs are causing major disruptions for American companies, including investment delays and layoffs.

The cost of President Donald Trump's trade war is starting to soar.

Trump has cheered billions "pouring into the coffers of the USA," but new data shows companies' costs starting to reach new records:

In October, US companies paid $6.2 billion in tariffs, up from $4.4 billion this past September and $3.1 billion in October 2017.

That's a 104% year-over-year increase, despite just a 13% jump in the value of imports, according to data compiled by Tariffs Hurt the Heartland, a pro-free-trade group, and the research firm The Trade Partnership.

The total payments in October is the largest monthly tariff collection amount in history, according to the groups.

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Tariff rates have been higher in the past, especially when duties were the primary source of government funds before the income tax was created in 1913. But inflation means the nominal value of the tariff collections today is much higher.

Trump's trade war is causing the amount in tariffs collected by the US Treasury to grow. Samantha Lee/Business Insider

Trump's tariffs on steel, aluminum, and nearly $250 billion worth of Chinese goods are clearly having an effect, the data showed:

Tariff collections on steel hit $446 million in October, and aluminum tariffs collected $134 million, according to Tariffs Hurt the Heartland.

Since the steel and aluminum tariffs kicked off in May, US firms have paid $3.1 billion to import the metals.

October also marked the first month that Trump's 10% tariff on roughly $200 billion worth of Chinese goods went into effect, adding onto 25% tariffs on $50 billion worth of Chinese goods that were imposed back in July. The new round caused a marked jump in tariff collections on those goods.

Before the tariffs being imposed, companies paid $0.4 billion a month to import the same goods, which jumped to $2.6 billion in October.

That means Trump's tariffs cost US firms $2.2 billion in additional costs in October alone and $4 billion more since China tariffs were first imposed in July.

In sum, US companies paid $7.4 billion more in tariffs as a result of Trump's trade war since the first tariffs went into place in May, and the amount is steadily increasing.

The cost to import goods subject to Trump's tariffs is skyrocketing. Samantha Lee/Business Insider

For his part, Trump has cheered the amount of money coming into the Treasury, tweeting about the collections as part of a trade tirade on Tuesday.

"We are right now taking in $billions in Tariffs. MAKE AMERICA RICH AGAIN," he said.

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But despite the president's proclamations, most economists warn that these costs are mostly being borne by American companies. In turn, a growing number of firms are reporting a delay in investments, slower pace of hiring, and even cost cuts such as layoffs. If cost increases continue, US companies have warned, consumer prices could also start to rise.

If that were to happen, or if Trump were to go through with threats to place tariffs on imported cars or more Chinese goods, the costs could eventually become a drag on US GDP growth.