Auto insurer Allstate Corp. on Monday said it would refund more than $600 million in insurance premiums, or up to 15% of what its customers pay in April and May. The company is covering fewer accidents as Americans stay home, and says it has tracked a 35% to 50% drop in driving mileage since states started issuing shelter-in-place and stay-at-home orders last month.

“You can just see it by state—boom, it dropped in mid-March,” Allstate CEO Tom Wilson told reporters on a conference call Monday morning. “It’s basically down everywhere across the country.”

He cited data from Allstate’s mobility-analytics subsidiary, Arity, which tracks 23 million vehicles. Not all of those are Allstate-insured cars or trucks; the company said its refunds would apply to 18 million customer policies.

“We’ve assumed that this will continue for a while,” Wilson said.

Separately on Monday, Midwestern auto insurer American Family Insurance said it would refund approximately $200 million in premiums, via one-time payments of $50 per vehicle it insures.

Chief operating officer Telisa Yancy also cited a drop-off in the miles its customers are racking up—and the resulting accidents they’re getting into: Customers “are driving less and experiencing fewer claims,” she said in a press release. “Because of these results, they deserve premium relief.”

Other big auto insurers followed suit throughout the week. On Tuesday, Liberty Mutual said it would refund approximately $250 million to auto-insurance customers, or 15 percent of their premiums for two months. Then Berkshire Hathaway’s Geico said it would refund approximately $2.5 billion to its 19 million auto- and motorcycle-insurance customers. That amounts to a 15 percent credit for all customers who renew or purchase a six-month policy through early October.

“This ongoing crisis has widespread effects that will linger,” Geico CEO Todd Combs said in a press release. “That is why we wanted to give this credit for at least six months.”

On Wednesday, several other insurers announced similar reductions or credits. Farmers Insurance said it would reduce the premiums its auto customers pay in April by 25 percent. Travelers said it would give back 15 percent of the premiums its customers pay in April and May. Progressive said it would spend $1 billion to give its auto-insurance customers credits worth approximately 20 percent of their premiums in April and May. USAA also said it would return $520 million to auto-insurance customers, through credits of 20 percent of their premiums in those two months.

Updated, April 7, 2020: This post has been updated to include statements from Liberty Mutual and Geico.

Updated, April 8, 2020: This post has been updated to include a statement from Farmers Insurance.

Updated, April 9, 2020: This post has been updated to include statements from USAA, Progressive, and Travelers.

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