Senate Republicans have run into a problem in passing their Obamacare replacement bill, which is that it would increase deductibles by thousands of dollars.

The new Congressional Budget Office report on the revised Senate health care bill was an important lesson in the tradeoffs in health insurance. Yes, it suggested that premiums could go down for some groups, which has been one of Republicans’ main goals. But because the “actuarial value” of the coverage could go down — meaning customers would have to pay much more of the medical costs themselves — the deductible for a low-income person could shoot up to $13,000.

Under current law, an individual making $56,800 would have a deductible of $5,000, while someone making $26,500 would have an $800 deductible.

“The way we come together, the way we bring together senators all across the ideological spectrum, is focusing on lowering premiums,” Sen. Ted Cruz said on Fox News on Friday.

“If we’re lowering premiums, that’s a win for everyone.”

Deductibles could become so high under the GOP plan, the CBO said, that many low-income people might decide not to purchase a health insurance plan, even if the premiums were low.

Another factor driving the higher deductibles under the Republican proposal, according to the CBO, is the elimination of Obamacare insurer payments known as cost sharing reduction subsidies. These payments reimburse insurers for giving discounted deductibles to low-income people.