The Short Answer
The Toyota Yaris wins this reliability test, but the Volkswagen Polo is not embarrassed. Across the 2024 public UK MOT record, the Polo posted a
Pass-Rate Split
This is the classic small-car argument: German feel against Japanese reputation. The Polo usually wins the cabin-touch test. The Yaris usually wins the pub answer on reliability. The useful bit is that the official UK records let us get past both cliches.
The Polo has the larger sample by a distance:
The Polo failed 21.11% of tests and had 4.82% recorded as PRS. The Yaris failed 17.39% and had 6.69% PRS. That split matters. The Toyota is less likely to fail outright, but it has more pass-after-rectification behaviour baked into the record. In plain English: more Yaris tests look like quick fixes at the station, fewer look like straight fails.
The headline gap is not massive.
This is exactly the kind of margin that should sharpen your inspection, not replace it. The Toyota wins the spreadsheet. The individual car still has to earn the money.
Where They Fail
The Polo’s failure list is very small-car, very British-road, very maintenance-sensitive.
Its top recorded failure reasons are:
- Rear registration plate lamp or light source missing or inoperative: 40,099
- Steering rack gaiter or ball-joint dust cover damaged or deteriorated: 36,979
- Transmission shaft constant velocity joint boot severely deteriorated: 27,533
- Suspension pin, bush or joint excessively worn: 27,163
- Windscreen or window damaged or seriously discoloured, but not badly enough to affect the driver’s view: 22,760
That is a front-end and rubber-parts story. Gaiters, CV boots, bushes and joints all sit high. None of that is surprising on an older supermini, but the concentration is useful. A Polo that knocks over bumps, has uneven tyre wear, or has repeated dust-cover advisories deserves a cold look underneath before you talk yourself into the nice dashboard.
The Yaris fails differently.
Its top recorded failure reasons are:
- Headlamp reflector or lens slightly defective: 19,603
- Lamp missing, inoperative, or more than half not functioning where multiple light sources are fitted: 13,833
- Tyre tread depth below the required limit: 12,013
- Wiper blade missing or not clearing the windscreen: 11,452
- Spring or spring component fractured or seriously weakened: 10,312
The Yaris list has more lamps, wipers and tyres near the top. Some of that is cheap-owner stuff. Some of it is age. The spring count is the one that deserves more respect, especially on older cars that have spent years meeting speed bumps and potholes.
The practical read is simple. On a Polo, listen and look at the suspension and steering parts first. On a Yaris, do not dismiss lamps and wipers as trivial if they repeat every year. Repeated cheap failures tell you how the car has been looked after.
Cohort Tells
All-age pass rates are useful, but they mix three very different markets: older budget cars, middle-aged used cars, and newer cars just entering regular MOT life.
For pre-2018 cars, the Polo passes 71.50% from 972,985 tests. The Yaris passes 73.50% from 600,585 tests. That is a proper Toyota win in the age band where most value buyers are shopping. It is also the closest thing here to the “100k miles” question, because these are the cars most likely to be old enough and used enough to be heading towards six figures.
For 2018-2020 cars, the Polo passes 85.10% from 147,278 tests. The Yaris passes 87.76% from 90,092 tests. The Toyota widens its lead slightly. This is the key band for buyers who want modern safety kit without paying nearly-new money. The Yaris is not just coasting on old reputation; it is better in this middle cohort too.
For 2021-on cars, the Polo passes 90.02% from 13,462 tests. The Yaris passes 93.47%, but from only 796 tests. The Toyota number is strong, but the sample is tiny compared with the Polo’s. Treat it as a signal, not a verdict by itself.
The cohort split is the bit that hurts the Polo. If the Toyota only won because the fleet was newer, lower-mileage or distorted by one age band, you would expect the advantage to vanish somewhere. It does not. The Yaris leads pre-2018, 2018-2020 and 2021-on.
That consistency is why the right answer is Toyota.
Mileage Tells
The Polo’s average mileage at test is 71,098. The Yaris average is 69,286. That gives the Toyota a 1,812-mile advantage on the all-age figure. The difference is real, but it is not big enough to explain the whole pass-rate gap by itself.
Look at the older cars. Pre-2018 Polos average 77,065 miles at test. Pre-2018 Yarises average 75,306. Again, the Polo is carrying about 1,759 extra miles. That matters, but it does not rescue the VW. The Yaris still posts a 73.50% pass rate against the Polo’s 71.50%.
For 2018-2020 cars, the mileage gap grows. The Polo averages 36,283 miles. The Yaris averages 29,659. That is a sizeable use difference, and it makes the 2018-2020 comparison less clean. A lower-mileage Yaris should pass more often. It does.
The 2021-on band flips the mileage point. The Polo averages 22,340 miles. The Yaris averages 25,591. Despite the Toyota carrying more miles in that small newer-car sample, it still passes more often. The sample is only 796 Yaris tests, so do not overbuild a theory from it. Still, it is not bad news for Toyota.
The buyer takeaway is sharper than the raw average. At 100k miles, you are not buying the average car in either dataset. You are buying the car that has lived through owners, tyres, suspension wear, lamp failures, skipped services and cheap repairs. The Yaris gives you a slightly better statistical starting point. The Polo asks for a more careful front-end inspection.
At high mileage, the badge matters less than the pattern. Repeated advisories are the car’s diary.
If the same Polo has gaiter, bush, CV boot and tyre advisories across several years, assume the front end is tired. If the same Yaris keeps coming back with lamps, wipers, tyres and springs, assume it has been maintained reactively rather than properly.
The Numbers We Trust
These figures come from the 2024 public UK MOT record, filtered to the Volkswagen Polo and Toyota Yaris model slugs used on this site. The headline pass rate is the recorded first-time pass rate in that model file. Test count is the number of recorded tests for the model in the same snapshot.
The clean comparison is:
- Volkswagen Polo: 1,133,725 tests, 73.49% pass rate, 71,098 average miles
- Toyota Yaris: 691,473 tests, 75.38% pass rate, 69,286 average miles
- Pass-rate gap: Yaris ahead by 1.89 percentage points
- Pre-2018 pass rates: Polo 71.50%, Yaris 73.50%
- 2018-2020 pass rates: Polo 85.10%, Yaris 87.76%
- 2021-on pass rates: Polo 90.02%, Yaris 93.47%
There are limits. The records do not tell you how the car was serviced, whether a private repair happened before the test, whether the tester was lenient on advisories, or whether a previous owner ignored a warning until it became a failure. They also do not price repairs. A cheap lamp failure and a suspension rebuild are not the same ownership pain.
That is why the top failure reasons matter. The Polo’s list points more strongly at steering, gaiters, CV boots and suspension wear. The Yaris list has more visible maintenance items, with springs as the bigger mechanical warning.
Use the data as a filter. Then read the actual MOT history.
If a car has one clean fail and then years of passes, fine. If it has the same advisory family appearing year after year, that is not bad luck. That is ownership style.
Verdict
The Toyota Yaris is the stronger reliability bet. It wins the all-age pass rate, wins the older-car cohort, wins the 2018-2020 cohort, and still looks strong in the newer-car slice despite the smaller sample.
The Polo is still a good supermini. It feels more solid than the Yaris in the places buyers touch every day, and a well-kept one can be a better car to live with than a tired Toyota. But the MOT record does not reward cabin feel. It rewards cars that turn up ready to pass.
For used buyers, the rule is this: choose the Yaris when condition and price are equal. Choose the Polo only when the individual car has a cleaner history, especially around steering gaiters, CV boots, suspension joints and tyres.