Iowa Just Added 5 MPH to Its Rural Roads. The Price Is About a Dozen Funerals.
On July 1, Iowa bumped rural two-lane speed limits from 55 to 60 mph, a change so small it barely registers on the speedometer but large enough to show up in the state's fatality statistics within a year. IIHS research covering every state from 1993 to 2013 found that each 5 mph increase in a state's maximum speed limit is associated with a 4% increase in traffic fatalities.[1] Iowa averages 337 road deaths a year, so four percent of that figure comes to roughly 13 additional funerals that would not otherwise have happened.
Thirteen people who are not hypothetical risk-model abstractions but actual Iowa residents whose deaths will trace, statistically, to a legislature that decided 55 was too slow. A separate study published in the American Journal of Public Health quantified the damage more broadly, finding that states which raised speed limits after the 1995 repeal of the national maximum saw a 3.2% increase in fatalities on all roads and a 9.1% spike on rural interstates specifically.[2] Those effects persisted for at least six years without fading or self-correcting, and the researchers noted that the increases compounded against every other safety improvement happening simultaneously.
Iowa's own data makes the context considerably grimmer, because the state logged 119 fatalities through June 12 of this year, already up 12.3% over the same period in 2025, which means deaths were climbing before the speed limit change even took effect.[3] Rural crashes account for 68.5% of Iowa's road deaths across the last five years, so the roads Iowa just made faster are already the roads that kill the most Iowans. A letter writer in the Des Moines Register celebrated the increase by arguing that modern vehicles are considerably safer than those from the 70 mph era, and he is right about the vehicles but wrong about the conclusion: the research explicitly shows that the fatality increase from higher speeds persists despite improvements in road design, crashworthiness, seat belt mandates, and child restraint use.[4] Going from 55 to 60 mph adds 19% more kinetic energy to every impact and stretches stopping distance by 22%, and no crumple zone revision erases that arithmetic.
So what does the trade actually buy a driver in practice? At 60 instead of 55, a 30-mile rural commute saves 2 minutes and 44 seconds, which means Iowa will exchange roughly 13 lives per year for under three minutes of convenience per trip. Each minute of time savings costs about 4.7 funerals annually, and at least eight other states are weighing similar increases right now.[5]
If you drive Iowa's rural two-lane roads: the posted number went up, but safe following distance did not get shorter, so add two full seconds of gap and check that your tires can handle the extra stopping demand. If you live in a state debating its own version of this bill, the body count math is not ambiguous and has been settled peer-reviewed science for two decades running.