Michigan Attorney General Dana Nessel is warning against propane price gouging during the winter deep freeze.
Propane is the primary heating fuel for about 320,000 Michigan households.
Prices are not regulated. But the Michigan Consumer Protection Act prohibits retailers from charging a price that is "grossly in excess of the price at which similar property or services are sold." Antitrust laws prohibit fuel providers from conspiring to arbitrarily fix prices.
The state monitors the propane market for what it calls irregularities that could cause supply or price disruptions.
Nessel says people should report suspected price gouging. The attorney general's office received hundreds of complaints during the polar vortex of 2013-14 and obtained about $600,000 worth of reimbursements or credits from two companies.
Propane currently sells for about $2.03 per gallon.