WASHINGTON, August 31 -
Border comparator - per-tank savings today
The largest US border-state gas price gap today is $1.21 per gallon between New Mexico and Arizona. For a 15-gallon fill, that's $18.08 saved per tank. Round-trip break-even mileage is shown below. [EIA · 31 Aug 2026]
Top 20 widest US border-state gaps today
| Pair | Cheap | Dear | Gap | 15-gal save | 26-gal save | Break-even mi (25 mpg) |
|---|---|---|---|---|---|---|
| NM vs AZ | $3.62 | $4.82 | $1.21 | $18.08 | $31.33 | 125 |
| ID vs WA | $4.27 | $5.26 | $0.99 | $14.90 | $25.82 | 87 |
| AZ vs CA | $4.82 | $5.52 | $0.70 | $10.45 | $18.12 | 54 |
| OR vs CA | $4.82 | $5.52 | $0.70 | $10.45 | $18.12 | 54 |
| NV vs CA | $4.82 | $5.52 | $0.70 | $10.45 | $18.12 | 54 |
| CO vs AZ | $4.13 | $4.82 | $0.69 | $10.37 | $17.97 | 63 |
| NM vs UT | $3.62 | $4.27 | $0.65 | $9.72 | $16.85 | 67 |
| ID vs OR | $4.27 | $4.82 | $0.56 | $8.36 | $14.48 | 49 |
| ID vs NV | $4.27 | $4.82 | $0.56 | $8.36 | $14.48 | 49 |
| UT vs AZ | $4.27 | $4.82 | $0.56 | $8.36 | $14.48 | 49 |
| UT vs NV | $4.27 | $4.82 | $0.56 | $8.36 | $14.48 | 49 |
| NM vs CO | $3.62 | $4.13 | $0.51 | $7.71 | $13.36 | 53 |
| OR vs WA | $4.82 | $5.26 | $0.44 | $6.54 | $11.34 | 34 |
| NE vs WY | $3.85 | $4.27 | $0.42 | $6.29 | $10.89 | 41 |
| ND vs MT | $3.85 | $4.27 | $0.42 | $6.29 | $10.89 | 41 |
| SD vs WY | $3.85 | $4.27 | $0.42 | $6.29 | $10.89 | 41 |
| SD vs MT | $3.85 | $4.27 | $0.42 | $6.29 | $10.89 | 41 |
| VA vs DC | $3.78 | $4.12 | $0.33 | $5.01 | $8.68 | 33 |
| WV vs MD | $3.78 | $4.12 | $0.33 | $5.01 | $8.68 | 33 |
| VA vs MD | $3.78 | $4.12 | $0.33 | $5.01 | $8.68 | 33 |
Featured pairs
Both states sit inside Central Atlantic (PADD 1B) and EIA surveys neither one on its own, so the weekly data shows no measurable gap across this border. Compare the tax stacks instead.
Method
Per-tank savings = (dearer state price - cheaper state price) x tank gallons. Break-even mileage = savings / fuel cost per mile. Assumes a 25 mpg vehicle and the cheap-state gasoline price for the detour.