Donald Trump singled out high premiums and deductibles during a rally in Cleveland on Saturday, saying that the law has impacted employment.
"Health insurance is being through the roof and [companies] are leaving the country," the GOP nominee said at the rally.
He also criticized Democratic nominee Hillary Clinton for pushing a government-run insurance option and other policies to enhance the law.
"Whether you are Hillary Clinton or anybody else, Obamacare is a disaster," said Trump, referring to sky-high premiums of up to 60-80 percent. "It is lousy healthcare. The deductibles are so high you don't want to use it anyways, but if you need it you are never going to use it so it is a horror show."
An independent estimate from the website acasignups.net pegs average rate hikes of 25 percent for 41 states, which includes individual plans sold off the exchange.
Some states are facing higher price hikes, such as Oklahoma that is experiencing hikes for 2017 of up to 70 percent.
Trump's healthcare plan focuses on enabling insurers to sell plans across state lines, and expand healthcare savings accounts that enable people to make tax-free contributions to be used for healthcare costs.