Is the 2021 BMW 3 SERIES reliable?

Excellent reliability. Very few MOT failures. 93% of BMW 3 SERIESs from 2021 passed their MOT first time in 2026, based on 908 tests. That's 11 points above the national average of 82%.

How much does a 2021 BMW 3 SERIES cost to run?

Estimated annual running cost is £1,487 (£124/month), including £1037 fuel, £195 road tax, £55 MOT, and £200 predicted repairs.

What is the MOT pass rate for a 2021 BMW 3 SERIES?

The 2021 BMW 3 SERIES has a 93% MOT pass rate based on 908 tests in 2026. This ranks 1558 out of 3373 cars from 2021.

Which year BMW 3 SERIES is most reliable?

The 2021 BMW 3 SERIES has the highest MOT pass rate at 93%. The least reliable year is 2000 at 77%.

BMW 3 SERIES (2021)

Q: What is the average mileage for a 2021 BMW 3 SERIES?

The average mileage for a 2021 BMW 3 SERIES is 28,473 miles, which is below the expected 37,000 miles for a 5-year-old car. This suggests lighter use than average, which generally means less wear on major components.

Running costs, reliability data, and common problems from 908 real MOT tests.

Annual Cost

£1,487

£124/month

MOT Pass Rate

93%

Excellent

Road Tax

£195

Flat rate/year

Insurance

Grp 18-32

1995cc Diesel

Great Choice

93% pass rate, £1487/year to run. 11 points above average.

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Diesel1995cc5 years old908 tests28k miles avg

Annual Running Costs

Fuel (Diesel, 1995cc)

~48 mpg

£1,037

Road Tax

Flat rate (post-2017)

£195

MOT Test

£55

Predicted Repairs

Low estimate due to excellent reliability

£200

Total per year£1,487

Per month£124/mo

Per week£29/wk

Based on 7,400 miles/year (UK average), current fuel prices, and repair likelihood from MOT data. Insurance not included.

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Reliability Verdict

93% MOT pass rate(Excellent)

0%National avg: 82%100%

Excellent reliability. Very few MOT failures. That's 11 points above the national average of 82%. It also outperforms the BMW brand average of 88%.

At 5 years old, 93% of BMW 3 SERIESs from 2021 passed their MOT first time in 2026. That's based on 908 tests across the UK. The average mileage at this age is 28,473 miles.

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How Does It Compare?

Rank among 2021 cars1558th of 3,373(top 46%)

Rank among BMW models368th of 1,564(top 24%)

vs national average+11%(82% avg)

vs 2021 cars average+1%(92% avg)

vs BMW average+5%(88% avg)

Mileage Analysis

28,473

Average miles

37,000

Expected for age

The average 2021 BMW 3 SERIES has 28,473 miles on the clock, which is below the expected 37,000 miles for a 5-year-old car. This suggests lighter use than average, which generally means less wear on major components.

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BMW 3 SERIES by Year

Year	Pass Rate	Tests	Avg Mileage
2021	93%	908	28,473 mi
2020	91%	7,526	41,101 mi
2019	91%	27,338	48,949 mi
2018	91%	19,475	56,573 mi
2017	90%	8,077	67,957 mi
2016	90%	48,559	80,506 mi
2015	88%	61,659	89,425 mi
2014	87%	63,059	101,192 mi
2013	85%	71,326	106,062 mi
2012	82%	68,955	111,893 mi
2011	81%	57,568	119,984 mi
2010	80%	52,791	122,709 mi
2009	80%	49,275	121,100 mi
2008	80%	48,705	125,171 mi
2007	80%	55,686	130,265 mi
2006	80%	40,353	136,490 mi
2005	78%	24,924	133,038 mi
2004	78%	18,555	124,569 mi
2003	78%	19,201	122,025 mi
2002	79%	14,796	121,727 mi
2001	77%	9,406	117,601 mi
2000	77%	4,799	114,997 mi
1999	78%	7,815	113,190 mi
1998	79%	6,287	122,358 mi
1997	79%	4,853	120,261 mi
1996	82%	3,215	116,915 mi
1995	80%	2,059	114,256 mi
1994	78%	1,263	115,103 mi
1993	82%	1,173	110,323 mi
1992	84%	1,309	110,038 mi
1991	82%	1,861	119,331 mi
1990	84%	3,316	122,194 mi

Similar Cars to Consider

FORD FOCUS

2019 · 1499cc Diesel

£1,500/year

89%

-4%

FORD KUGA

2019 · 1997cc Diesel

£1,482/year

91%

-2%

VOLKSWAGEN POLO

2019 · 1598cc Diesel

£1,500/year

89%

-4%

FORD TRANSIT CUSTOM

2019 · 2000cc Diesel

£1,632/year

87%

-6%

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About the 2021 BMW 3 SERIES

The 2021 BMW 3 SERIES is a premium with a 1995cc diesel engine. 908 of these vehicles were MOT tested in 2026, making it a less common model in the UK market. Among all cars from 2021, the average MOT pass rate is 92%, and this model beats that benchmark.

With an average of 28,473 miles at 5 years old, BMW 3 SERIES owners tend to use this car less than the typical driver.

2021 BMW 3 SERIES Fuel Costs

The 1995cc diesel engine offers a reasonable balance between performance and economy. Expect around 48 mpg in mixed driving, which works out to roughly £1,037 per year at current diesel prices of 148p per litre (based on 7,400 miles per year). Diesel cars of this age should have their DPF (diesel particulate filter) checked, as replacements can be costly.

What does it cost to own a 2021 BMW 3 SERIES?

Total estimated annual running cost is £1,487 (£124/month), broken down as £1037 fuel, £195 road tax, £55 MOT, and £200 predicted repairs. The low repair estimate reflects the excellent 93% pass rate. These cars rarely fail their MOT, so unexpected bills are less likely.

BMW 3 SERIES Reliability Trend

Newer BMW 3 SERIESs show better MOT pass rates than older ones, with an average improvement of 6 percentage points.

Buying a Used 2021 BMW 3 SERIES

At 5 years old, the BMW 3 SERIES offers good value with plenty of life remaining. Most manufacturer warranties will have expired, so a pre-purchase inspection is worth the cost.

Common Issues to Watch For

Based on the 2021 BMW 3 SERIES's fuel type, age, and engine size, these are the most likely problem areas to check.

DPF (Diesel Particulate Filter)

Watch out

Short journeys clog the DPF. Replacement costs £1,000-£2,500. Check the DPF warning light and ask about driving patterns.

Turbo Wear

Medium risk

Diesel turbos work harder and wear faster. Listen for whining noises and check for oil leaks around the turbo housing.

AdBlue System

Medium risk

Post-2015 diesels use AdBlue for emissions. Sensor failures and tank heater issues are common. Budget £200-£500 for repairs.

EGR Valve

Low risk

Exhaust Gas Recirculation valves clog with carbon deposits, causing rough running and poor economy. Cleaning costs £150-£300, replacement £300-£600.

Service History

Low risk

Always request a full service history. Regular servicing is the single best indicator of how well a car has been maintained, regardless of mileage.

Running Costs Compared

How the 2021 BMW 3 SERIES stacks up against similar cars for annual running costs, insurance, and tax.

Car	Pass Rate	Fuel/yr	Tax/yr	Insurance	Total/yr
BMW 3 SERIES(2021)	93%	£1037	£195	Grp 18-32	£1487
FORD FOCUS(2019)	89%	£905	£190	Grp 12-25	£1500+£13
FORD KUGA(2019)	91%	£1037	£190	Grp 18-32	£1482-£5
VOLKSWAGEN POLO(2019)	89%	£905	£190	Grp 12-25	£1500+£13
FORD TRANSIT CUSTOM(2019)	87%	£1037	£190	Grp 18-32	£1632+£145

Estimates based on 7,400 miles/year, current fuel prices, and MOT data. Insurance groups are indicative. Actual costs vary by driver, location, and usage.