Iowa's new 60 mph speed limit takes effect July 1 on some state highways and rural paved roads. But before drivers step on the gas, state officials said they need to wait for the speed limit signs to catch up.
The Iowa Department of Transportation (DOT) estimated it will take at least a week to update about 1,800 speed limit signs by covering them with aluminum overlays. On county roads, the process could take considerably longer to upgrade the approximately 3,500 signs.
“We really want motorists to follow the posted speed limit,” said, Daniel Yeh, director of government and community relations at the Iowa DOT. “Not every 55 mph road is going to increase to 60. Some of the roads will not increase, because we already have a study — or will have a study very soon — that says they need to stay at 55.”
The Iowa State Patrol also reminded motorists to obey the posted speed limit until new signs are in place.
Counties worry about costs
Some county leaders said they worried about the expense of complying with the new law. The nonpartisan Legislative Services Agency estimated it will cost about $825,000 to update all the signs throughout the state.
During a June 23 board meeting, Woodbury County Engineer Laura Sievers told supervisors it could take months and thousands of dollars to modify road signs. Rather than replacing them, Woodbury County plans to use stickers to cover the outdated numbers.
“We’re trying to survive this change, that does nickel and dime our budget quite a bit here and there,” Sievers said.
Other counties have raised similar concerns about what Sievers called an “unfunded mandate.”
Brian Moore, executive director of the Iowa County Engineers Association Service Bureau, said more work is needed to determine whether curves and passing zones should be adjusted to accommodate the higher speed limit.
“People need to be patient with the state and the counties as they work through getting the signage out appropriately,” Moore said. “The unpaved gravel roads are still 55 because that’s a different code section.”
Safety concerns remain
Beyond the price tag, some officials and safety advocates question whether higher speed limits will lead to more serious crashes. A 2019 study by the Insurance Institute for Highway Safety found that increasing speed limits by 5 mph led to a measurable increase in traffic fatalities.
The U.S. Department of Transportation also reported that speeding was a factor in about 20% of fatal crashes in Iowa between 2014 and 2023.
Some have also expressed concern about reduced reaction time on rural two-lane highways, where motorists can encounter slow-moving farm equipment.
Rick Young, a Hamilton County supervisor, told Radio Iowa he believed the higher speed limit could undermine years of progress in reducing traffic deaths.
“We have lowered the death rate on highways, compared to multiple years prior, so it’s unfortunate,” Young said. “Many of us believe that the Legislature chose to do that for the lack of safety.”
Gov. Kim Reynolds signed Senate File 378 on June 2 after it passed the Legislature, saying the change reflects what she’s been hearing from Iowans.
“This is grassroots-driven,” Reynolds said. “If you look at social media, they’re pretty excited that it’s going to be legal to drive what they’ve been driving.”
The new law follows a major traffic safety change. After Iowa banned the use of handheld electronic devices while driving, the state recorded its lowest annual number of traffic deaths in a century. According to the Iowa DOT, 260 died on Iowa roads in 2025, about 100 fewer than the previous year.
