List of auxiliary Interstate Highways
This is a list of auxiliary Interstate Highways. These are interstate highways with three digits.
| Hawaii |
| H-201 |
| California |
| I-105 |
| I-205 |
| I-405 |
| I-505 |
| I-605 |
| I-805 |
| I-905 |
| Oregon |
| I-105 |
| I-405 |
| Oregon-Washington |
| I-205 |
| Washington |
| I-405 |
| I-705 |
| California |
| I-110 |
| I-210 |
| I-710 |
| Florida |
| I-110 |
| Louisiana |
| I-110 |
| I-210 |
| I-310 |
| I-510 |
| I-610 |
| Mississippi |
| I-110 |
| Texas |
| I-110 |
| I-410 |
| I-610 |
| California |
| I-215 |
| Montana |
| I-115 |
| Nevada |
| I-215 |
| I-515 |
| Utah |
| I-215 |
| Georgia |
| I-516 |
| Georgia-South Carolina |
| I-520 |
| Louisiana |
| I-220 |
| Mississippi |
| I-220 |
| Texas |
| I-820 |
| Tennessee |
| I-124 |
| Colorado |
| I-225 |
| South Carolina |
| I-126 |
| I-526 |
| Iowa-Nebraska |
| I-129 |
| Missouri |
| I-229 |
| South Dakota |
| I-229 |
| Arkansas |
| I-430 |
| I-530 |
| I-630 |
| Iowa |
| I-235 |
| Kansas |
| I-135 |
| I-235 |
| I-335 |
| Kansas-Missouri |
| I-435 |
| I-635 |
| Minnesota-Wisconsin |
| I-535 |
| Oklahoma |
| I-235 |
| Texas |
| I-635 |
| California |
| I-238 |
| Arkansas |
| I-440 |
| I-540 |
| North Carolina |
| I-140 |
| I-240 |
| I-440 |
| I-540 |
| I-840 |
| Oklahoma |
| I-240 |
| Tennessee |
| I-140 |
| I-240 |
| I-440 |
| I-640 |
| I-840 |
| Oklahoma |
| I-244 |
| I-444 |
| Illinois |
| I-155 |
| I-355 |
| Illinois-Missouri |
| I-255 |
| Missouri-Tennessee |
| I-155 |
| Alabama |
| I-359 |
| I-459 |
| I-759 |
| Kentucky |
| I-264 |
| Virginia |
| I-264 |
| I-464 |
| I-564 |
| I-664 |
| Alabama |
| I-165 |
| I-565 |
| Indiana |
| I-465 |
| I-865 |
| Indiana-Kentucky |
| I-265 |
| Kentucky |
| I-165 |
| Indiana |
| I-469 |
| Kentucky |
| I-169 |
| Mississippi-Tennessee |
| I-269 |
| Texas |
| I-169 |
| I-369 |
| Colorado |
| I-270 |
| Illinois-Missouri |
| I-270 |
| Kansas |
| I-470 |
| Kansas-Missouri |
| I-670 |
| Maryland |
| I-270 |
| I-270 Spur |
| I-370 |
| Missouri |
| I-170 |
| I-470 |
| Ohio |
| I-270 |
| I-670 |
| Ohio-West Virginia |
| I-470 |
| Kentucky-Ohio |
| I-471 |
| Ohio |
| I-271 |
| Illinois |
| I-172 |
| Illinois |
| I-474 |
| Florida |
| I-175 |
| I-275 |
| I-375 |
| Georgia |
| I-475 |
| I-575 |
| I-675 |
| Indiana-Kentucky-Ohio |
| I-275 |
| Michigan |
| I-275 |
| I-375 |
| I-475 |
| I-675 |
| Ohio |
| I-475 |
| I-675 |
| Tennessee |
| I-275 |
| Pennsylvania |
| I-176 |
| I-276 |
| I-376 |
| I-476 |
| Pennsylvania-New Jersey |
| I-676 |
| North Carolina |
| I-277 |
| Ohio |
| I-277 |
| New Jersey-New York |
| I-278 |
| New York |
| I-678 |
| Pennsylvania |
| I-279 |
| I-579 |
| California |
| I-280 |
| I-380 |
| I-580 |
| I-680 |
| I-880 |
| I-980 |
| Illinois |
| I-180 |
| Illinois-Iowa |
| I-280 |
| Iowa |
| I-380 |
| I-880 |
| Iowa-Nebraska |
| I-480 |
| I-680 |
| Nebraska |
| I-180 |
| Nevada |
| I-580 |
| New Jersey |
| I-280 |
| Ohio |
| I-280 |
| I-480 |
| I-680 |
| Pennsylvania |
| I-180 |
| I-380 |
| Wyoming |
| I-180 |
| New York |
| I-481 |
| I-781 |
| Virginia |
| I-381 |
| I-581 |
| Washington |
| I-182 |
| Pennsylvania |
| I-283 |
| Connecticut |
| I-384 |
| Connecticut-New York |
| I-684 |
| Idaho |
| I-184 |
| Georgia |
| I-185 |
| I-285 |
| I-985 |
| North Carolina |
| I-285 |
| I-485 |
| I-785 |
| South Carolina |
| I-185 |
| I-385 |
| I-585 |
| New Jersey-New York |
| I-287 |
| New York |
| I-587 |
| I-787 |
| Vermont |
| I-189 |
| Illinois |
| I-190 |
| I-290 |
| Massachusetts |
| I-190 |
| I-290 |
| New York |
| I-190 |
| I-290 |
| I-390 |
| I-490 |
| I-590 |
| I-690 |
| I-790 |
| I-890 |
| I-990 |
| Ohio |
| I-490 |
| South Dakota |
| I-190 |
| Connecticut |
| I-291 |
| I-691 |
| Massachusetts |
| I-291 |
| I-391 |
| New Hampshire |
| I-293 |
| I-393 |
| Illinois |
| I-294 |
| Michigan |
| I-194 |
| Minnesota |
| I-394 |
| I-494 |
| I-694 |
| Wisconsin |
| I-794 |
| I-894 |
| Connecticut-Massachusetts |
| I-395 |
| Delaware |
| I-495 |
| Delaware-New Jersey |
| I-295 |
| District of Columbia |
| I-695 |
| District of Columbia-Maryland |
| I-295 |
| District of Columbia-Maryland-Virginia |
| I-495 |
| District of Columbia-Virginia |
| I-395 |
| Florida |
| I-195 |
| I-295 |
| I-395 |
| I-595 |
| Maine |
| I-195 |
| I-295 |
| I-395 |
| Maryland |
| I-195 |
| I-395 |
| I-695 |
| I-795 |
| I-895 |
| Massachusetts |
| I-495 |
| Massachusetts-Rhode Island |
| I-195 |
| I-295 |
| New Jersey-Pennsylvania |
| I-195 |
| New York |
| I-295 |
| I-495 |
| I-695 |
| I-895 |
| North Carolina |
| I-295 |
| I-795 |
| Virginia |
| I-195 |
| I-295 |
| Michigan |
| I-196 |
| I-296 |
| I-696 |
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