Should I check the MOT history before buying a 2018 Seat Mii?

Yes. Look for recurring advisories — slow-building issues like corrosion or brake wear patterns show up years before they become failures. A full MOT history analysis will highlight patterns that a single test result won't reveal.

What corrosion should I look for when inspecting a 2018 Seat Mii?

Check brake pipes, sills, subframes, and chassis legs. Surface rust is normal at this age; structural rust is a serious problem that is expensive to fix and can fail an MOT.

How are tyres and brakes typically on a 2018 Seat Mii?

Tyres and brakes are the most common advisory items on vehicles of this age. Budget for replacement if they are near the limit, and factor this into your offer price.

Is the 2018 Seat Mii reliable?

Based on MOT data from 1,283 vehicles, the 2018 Seat Mii has a first-time MOT pass rate of 89.1%, indicating generally reliable for its class. Always check the full MOT history of any specific vehicle before buying.

What are common problems with the 2018 Seat Mii?

The most frequently recorded MOT issues on the 2018 Seat Mii are: Offside Rear Tyre slightly damaged/cracking or perishing (46% of vehicles), Nearside Rear Tyre slightly damaged/cracking or perishing (42.2% of vehicles), Nearside Front Tyre worn close to legal limit/worn on edge (37.7% of vehicles). These figures are based on actual MOT test records — search a specific registration on CarHunch to see its individual history.

Do I need an HPI check when buying a 2018 Seat Mii?

Yes. The MOT history will not show outstanding finance, insurance write-offs, or stolen status. An HPI check covers these areas and should be part of any used car purchase.

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Seat Mii (2018)

1,283 real MOT outcomes analysed • 89.1% first-time pass rate

2018 Seat Mii

CarHunch analysed 1,283 real MOT records for the 2018 Seat Mii. Real test outcomes — pass rates, defect profiles, mileage data — from verified DVLA records. Updated as new MOTs are recorded.
Which year to buy? →

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AI Analysis Reliability Overview Common Issues Check a Specific Reg Buyer's Checklist Mileage Distribution Still on the Road MOT Averages Colour Breakdown Compare Models

The 2018 SEAT MII is a genuinely reliable small car, with an 88.6% first-time MOT pass rate that sits comfortably 8.6 percentage points above the UK average—and only 13% of vehicles have ever recorded a dangerous defect, which is well below concerning levels. This is a car that typically passes its test without fuss.

These MIIs are running at a sensible 25,030 miles median for their age, suggesting moderate use and good owner care, and when they do fail MOT they average just 0.73 failures per vehicle, indicating minor rather than systemic problems. Before buying, request the full MOT history to check for any pattern of advisories (averaging 4.1 per car), as this tells you far more about maintenance habits than a single test result.

The 2018 Seat Mii passes its MOT first time more often than most UK vehicles (89.1% vs ~80% average) — and when it does fail, it's usually something minor and cheap to fix.

⚠️ Around 1 in 8 of these vehicles have had a dangerous MOT failure at some point — usually tyres or brakes, and often a one-off issue rather than a persistent problem. The group stats won't tell you which one you're looking at.

First-time pass

89.1%

UK average ~80%

Better than average

Dangerous (ever)

13%

At least once in MOT history

Check this vehicle

Avg failures / car

0.73

Over 5.7 tests on record

Moderate

Typical mileage

25k

Middle half: 17k–35k

For context

✅ Good baseline reliability. A 89.1% first-time pass rate puts this well above the UK average — it's a well-sorted vehicle in this age bracket.

🔧 Expect consumable spend. An average of 4.1 advisories per vehicle tells you wear items (tyres, brakes) get flagged regularly. Budget for them — they're not surprises.

🔍 The dangerous defect figure is real. Most are one-off tyre failures or brake issues — not structural problems. But it's exactly why checking the individual vehicle's history is essential, not optional.

These stats describe 1,283 vehicles as a group. The specific vehicle you're looking at could be the one good example or the one outlier. Run its registration to find out.

A solid choice — agree?

What tends to go wrong

Across 1,283 vehicles — figures show how many had each issue flagged at least once in their MOT history.

Tyre wear 46%

Offside Rear Tyre slightly damaged/cracking or perishing · Nearside Rear Tyre slightly damaged/cracking or perishing · Nearside Front Tyre worn close to legal limit/worn on edge · …

Budget for a full set — on a vehicle this age, tyres are expected consumables. An inspection will confirm how much is left.

Brake wear 17%

Front Brake pad(s) wearing thin · Front Brake disc worn, pitted or scored, but not seriously weakened · Front Brake disc worn, but not excessively · …

Ask the seller when brakes were last serviced. If they don't know, factor in the cost.

Lighting 9.3%

Vehicles internal headlight adjuster altered to recheck lights · Nearside Front Position lamp not working · Offside Front Position lamp not working

Usually cheap to fix. Worth confirming all lights work before collecting.

Other issues 7.8%

COVID-19 6 MONTH EXTENSION

Data covers a 3-year window centred on 2018.

See this vehicle's full MOT history & AI hunches

Spot recurring advisories, hidden issues, and how it compares to 1,283 Seat Mii cars.

Before you buy a 2018 Seat Mii

Based on MOT data from 1,283 vehicles — here's what to check.

📋 Check the full MOT history. 13% of these vehicles have had a dangerous defect recorded - recurring advisories often signal problems years before they become failures.
Search the reg on CarHunch for the full MOT history, reliability stats and a free AI-powered analysis of that exact vehicle.
🔍 Brake pipes, sills and subframes are the key areas on a vehicle this age — structural rust is hard to spot without getting underneath. A mechanic will check all of this before you commit, and give you a concrete basis to negotiate on price. Inspection →
📄 Outstanding finance, insurance write-offs and clocking won't appear in the MOT records — a dedicated history check covers all of this. Our link gets you 20% off automatically. History Get 20% off via CarHunch

Colour Breakdown

Based on 17,857 Seat Mii vehicles registered in the UK — across all years. From DVLA registration records.

White 30.6%

5,471

Red 24%

4,294

Black 15.3%

2,732

Silver 9%

1,611

Beige 6.8%

1,213

Blue 5.7%

1,019

Yellow 5.3%

949

Purple 3.1%

554

Cream 0.1%

Gold 0%

Mileage Distribution

Most 2018 Seat Mii vehicles sit in the blue band. If the vehicle you're looking at is outside it, it's either unusually low or high mileage for its age.

25,030

typical

17,008

low mileage

34,731

high mileage

Half of all 2018 Seat Mii vehicles fall between 17,008 and 34,731 miles.

Is the mileage you're seeing normal?

✓ Under 17,008 miles — lower than most. Could be great, or could be a vehicle that rarely moved. Check test frequency and mileage progression in the MOT history.

✓ 17,008–34,731 miles — normal for age. This is where most 2018 Seat Miis sit.

⚠ Over 46,886 miles — higher than typical. Not necessarily a problem, but check service history and look out for advisory build-up on tyres and brakes.

2018 Seat Mii — Still on the Road

Almost all 2018 Seat Miis are still on the road.

Strong survival — 1,235 vehicles still getting MOTs in 2025, 99% of the peak.

Based on vehicles from this manufacture year that had at least one MOT test in each calendar year. Data from 2021–2025.

MOT History Averages

5.7

Avg MOT tests per vehicle

0.73

Avg failures per vehicle

4.1

Avg advisories per vehicle

Other model years — Seat Mii: All Mii years → Which year to buy? →

2012 2013 2014 2015 2016 2017 2019

Or browse all models: Seat →

Compare with another model

See how the 2018 Seat Mii stacks up against a rival.

A solid choice — agree?