New York leads the US ranking for rough highway travel
Compare the share of measured National Highway System travel on rough pavement in all 50 states.
Compiled by CarInspectionChecklist.com · 2024 data · Updated October 6, 2026
- New York: highest share
- 21.94% Measured NHS travel, 2024
- New Hampshire: lowest
- 2.19% Measured NHS travel, 2024
- All 50 states combined
- 9.46% Travel-weighted share, 2024
Source: FHWA Highway Statistics 2024, HM-47A. Rough means IRI above 170 inches per mile. Unreported roughness is excluded; the NHS is a defined highway network, not every road.
Where was rough-road travel most common?
New York led at 21.94%, followed by Hawaii at 21.47% and California at 20.68%. The difference between New York and Hawaii was 0.46 percentage points, calculated before rounding.
New Hampshire had the lowest share at 2.19%, followed by Georgia at 2.31% and Minnesota at 2.33%. “Smoothest” in this ranking means the lowest rough-travel share; it does not establish that every road is smooth.
Across the 50 states, 9.46% of reported NHS travel was in the rough bands. That weights each state's contribution by travel, rather than taking a simple average of state percentages.
How does each state rank?
50 of 50 states shown
| Rank | Rough road length | Unknown travel* | ||
|---|---|---|---|---|
| 1 | New York | 21.94% | 20.03% | 3.71% |
| 2 | Hawaii | 21.47% | 24.00% | 0.43% |
| 3 | California | 20.68% | 28.65% | 0.23% |
| 4 | Rhode Island | 17.92% | 31.75% | 0.88% |
| 5 | Louisiana | 16.56% | 16.94% | 2.56% |
| 6 | Massachusetts | 15.71% | 24.92% | 2.83% |
| 7 | Illinois | 12.45% | 13.43% | 0.01% |
| 8 | Washington | 12.37% | 15.24% | 0.21% |
| 9 | Colorado | 12.34% | 10.83% | 0.00% |
| 10 | Wisconsin | 12.33% | 13.85% | 0.36% |
| 11 | Pennsylvania | 12.17% | 13.33% | 0.00% |
| 12 | New Jersey | 12.02% | 21.26% | 0.00% |
| 13 | Nebraska | 11.48% | 6.77% | 0.32% |
| 14 | Maryland | 10.47% | 16.34% | 0.18% |
| 15 | Michigan | 9.67% | 9.83% | 4.64% |
| 16 | Texas | 8.42% | 8.74% | 1.04% |
| 17 | Iowa | 7.42% | 8.54% | 0.15% |
| 18 | Virginia | 7.14% | 8.17% | 0.00% |
| 19 | New Mexico | 7.13% | 7.19% | 0.01% |
| 20 | Alaska | 7.06% | 14.47% | 0.97% |
| 21 | Oregon | 6.91% | 5.86% | 0.15% |
| 22 | Mississippi | 6.71% | 8.47% | 0.00% |
| 23 | Oklahoma | 6.58% | 6.96% | 2.91% |
| 24 | Arizona | 6.53% | 8.89% | 1.05% |
| 25 | Arkansas | 6.29% | 5.68% | 1.88% |
| 26 | Ohio | 6.23% | 8.96% | 0.06% |
| 27 | Delaware | 5.62% | 6.25% | 2.30% |
| 28 | West Virginia | 5.53% | 7.34% | 0.12% |
| 29 | Connecticut | 5.53% | 11.16% | 0.02% |
| 30 | Missouri | 5.01% | 4.80% | 0.04% |
| 31 | Nevada | 4.29% | 2.53% | 0.00% |
| 32 | South Carolina | 4.26% | 5.10% | 0.88% |
| 33 | North Carolina | 4.24% | 5.08% | 0.51% |
| 34 | Utah | 4.21% | 2.96% | 0.81% |
| 35 | Indiana | 4.17% | 3.48% | 0.68% |
| 36 | Maine | 3.95% | 4.89% | 0.29% |
| 37 | North Dakota | 3.81% | 2.37% | 0.06% |
| 38 | Montana | 3.79% | 3.49% | 0.00% |
| 39 | Wyoming | 3.72% | 1.93% | 1.24% |
| 40 | Vermont | 3.69% | 4.21% | 0.73% |
| 41 | Tennessee | 3.63% | 5.02% | 6.02% |
| 42 | South Dakota | 3.60% | 2.61% | 0.58% |
| 43 | Kentucky | 3.59% | 2.79% | 1.30% |
| 44 | Idaho | 3.49% | 4.13% | 0.31% |
| 45 | Kansas | 3.42% | 2.36% | 0.80% |
| 46 | Florida | 3.06% | 3.76% | 0.13% |
| 47 | Alabama | 2.90% | 2.61% | 0.77% |
| 48 | Minnesota | 2.33% | 3.02% | 0.00% |
| 49 | Georgia | 2.31% | 2.73% | 0.00% |
| 50 | New Hampshire | 2.19% | 3.95% | 0.00% |
*Unknown travel is the share of reported plus unreported NHS travel without an IRI value. The ranking excludes it from the denominator. Road-length shares also exclude unreported length. These percentages measure different things.
CarInspectionChecklist.com. Rough-road travel by state, FHWA 2024. Compiled October 6, 2026. https://carinspectionchecklist.com/research/rough-roads/
How was the ranking calculated?
We used the 2024 edition of the Federal Highway Administration's Highway Statistics, tables HM-47A (daily travel) and HM-47 (road length). Both are dated November 2025. The FHWA series index still listed 2024 as its latest edition when we downloaded the tables on October 6, 2026.
For each state we added the rural and urban TOTAL NHS figures on sheets 2 and 4. “Rough” is our stated cut: IRI bands 171–194, 195–220 and over 220 inches per mile. IRI measures ride roughness; FHWA says a comprehensive pavement assessment also needs measures of pavement distress.
The ranked percentage is 100 × daily travel in those three bands ÷ TOTAL REPORTED daily travel. HM-47A reports daily travel in thousands of vehicle-miles; the common unit cancels in the percentage. We used the reported totals rather than rebuilding them from rounded bands. Published dashes contribute no reported quantity. The CSV keeps the rough, reported and unreported quantities.
The road-length comparison uses the same bands and formula with HM-47 miles. It is not the ranking measure and is not lane mileage. Unreported travel and length are excluded from the measured denominators, not classified as smooth; FHWA notes that unreported sections may include structures and unpaved miles.
We rank all 50 states from highest to lowest using unrounded travel shares, excluding DC and territories. Exact ties would share a competition rank and be displayed alphabetically; none occur in this extraction. Displayed percentages are rounded to two decimals. The combined figure sums rough travel across the 50 states and divides it by their summed reported travel.
What does it leave out?
The National Highway System includes Interstates and other important routes. It does not cover every state or local road. This is a comparison of measured 2024 travel, not a count of potholes, a ranking of crash risk, an estimate of repair costs or a forecast of Thanksgiving traffic, weather or 2026 pavement conditions. Unreported roughness and reporting differences can affect comparisons; a low measured share does not prove unreported sections are smooth.
What should a used-car buyer check?
A statewide percentage cannot tell you the condition of a particular car. If its history includes rough-road driving, give the suspension, tyres and alignment attention: look for uneven tyre wear and note pulling, vibration or unusual suspension noises during a test drive. Ask a mechanic to assess those observations in a pre-purchase inspection; they do not prove rough roads caused a fault.
Use our used-car inspection checklist to organize those checks. For other data references, see used-car statistics.