Owners filed 2,598 complaints about the 2015–2025 Kia Optima with the National Highway Traffic Safety Administration (NHTSA), the 37th-most of any vehicle in our Car Problem Index. The 2015 model year drew the most (1,006), and the single most-reported problem area is engine, named in 59% of complaints.
Key findings
- Worst model year: 2015, with 1,006 complaints, led by engine (622).
- Spike years: 2015 (3.9× the typical year), 2016 (3.0× the typical year).
- Earliest-failing area: brakes complaints came at a median of 22k mi on the odometer.
- Fire and crash reports: 120 complaints mention a fire and 98 mention a crash; owners reported 80 injuries and 2 deaths.
Kia Optima complaints by model year
| Model year | Complaints | Top problem areas | Median mileage | Crashes | Fires |
|---|---|---|---|---|---|
| 2015 | 1,006 | Engine (622), Electrical system (135), Body structure (76) | 80k mi | 31 | 74 |
| 2016 | 754 | Engine (424), Electrical system (102), Transmission / powertrain (73) | 68k mi | 27 | 19 |
| 2017 | 255 | Engine (164), Electrical system (25), Transmission / powertrain (21) | 54k mi | 4 | 9 |
| 2018 | 232 | Engine (131), Electrical system (33), Transmission / powertrain (18) | 45k mi | 10 | 10 |
| 2019 | 206 | Engine (88), Automatic emergency braking / collision warning (36), Electrical system (23) | 30k mi | 20 | 6 |
| 2020 | 145 | Engine (98), Transmission / powertrain (26), Electrical system (13) | 60k mi | 6 | 2 |
Newer model years have had less time on the road, so their counts are lower partly because owners have had fewer years to report problems.
Most-reported Kia Optima problems, and what they cost to fix
| Problem area | Complaints | Share | Median mileage | Repair estimate |
|---|---|---|---|---|
| Engine | 1,527 | 59% | 82k mi | Engine repair cost |
| Electrical system | 331 | 13% | 62k mi | Alternator / electrical repair cost |
| Transmission / powertrain | 204 | 8% | 55k mi | Transmission repair cost |
| Fuel system | 158 | 6% | 86k mi | Fuel pump repair cost |
| Body structure | 143 | 6% | 44k mi | — |
| Steering | 122 | 5% | 39k mi | Power steering repair cost |
| Brakes | 119 | 5% | 22k mi | Brake repair cost |
| Speed control / acceleration | 104 | 4% | 39k mi | — |
One complaint can name several problem areas, so shares add up to more than 100%.
What this data can and can't tell you
These are unverified reports that owners submitted to NHTSA, counted by model year. They are not defect findings, and they aren't adjusted for sales: a best-selling vehicle collects more complaints simply because more of them are on the road. Use the counts to compare model years of the same vehicle and to see which systems owners complain about most, not to compare how reliable two different models are. See the full methodology.
Other Kia models in the index
- Kia Sorento (4,270)
- Kia Soul (3,124)
- Kia Telluride (1,977)
Source: NHTSA Office of Defects Investigation, consumer complaint files (nhtsa.gov), model years 2015–2025, retrieved 2026-09-23. Free to cite with a link to this page.