Below are the top 25-most researched new and used cars on KBB.com during the month of September.
| RANK | NEW | RANK | USED | |
| 1 | HONDA CR-V | 1 | HONDA ACCORD | |
| 2 | TOYOTA CAMRY | 2 | HONDA CIVIC | |
| 3 | HONDA CIVIC | 3 | TOYOTA CAMRY | |
| 4 | HONDA ACCORD | 4 | FORD F150 | |
| 5 | NISSAN ALTIMA | 5 | TOYOTA COROLLA | |
| 6 | HYUNDAI ELANTRA | 6 | BMW 3 SERIES | |
| 7 | FORD F150 | 7 | NISSAN ALTIMA | |
| 8 | FORD ESCAPE | 8 | CHEVROLET SILVERADO 1500 | |
| 9 | MAZDA MAZDA3 | 9 | FORD MUSTANG | |
| 10 | HYUNDAI SONATA | 10 | FORD F250/F350/F450 SUPER DUTY | |
| 11 | CHEVROLET EQUINOX | 11 | JEEP WRANGLER | |
| 12 | MAZDA CX-5 | 12 | VOLKSWAGEN JETTA | |
| 13 | FORD FOCUS | 13 | JEEP GRAND CHEROKEE | |
| 14 | FORD FUSION | 14 | TOYOTA TACOMA | |
| 15 | VOLKSWAGEN JETTA | 15 | FORD FOCUS | |
| 16 | TOYOTA HIGHLANDER | 16 | HONDA CR-V | |
| 17 | KIA OPTIMA | 17 | RAM 1500 | |
| 18 | TOYOTA COROLLA | 18 | FORD EXPLORER | |
| 19 | CHEVROLET CRUZE | 19 | FORD RANGER | |
| 20 | TOYOTA RAV4 | 20 | FORD TAURUS | |
| 21 | LEXUS RX | 21 | CHEVROLET IMPALA | |
| 22 | TOYOTA TACOMA | 22 | NISSAN MAXIMA | |
| 23 | KIA SORENTO | 23 | FORD ESCAPE | |
| 24 | JEEP WRANGLER | 24 | HONDA ODYSSEY | |
| 25 | JEEP GRAND CHEROKEE | 25 | CHEVROLET MALIBU | |
