Failed your MOT? Learn about the free 10-day retest rule, what gets rechecked, partial vs full retests (VT20 vs VT30), and how to avoid paying twice.
Failed your MOT? You might be entitled to a free retest. Understanding the retest rules can save you the full MOT fee (£54.85 for cars) and ensure you only pay for the repairs, not multiple tests.
This guide explains the 10 working day rule, partial vs full retests, what gets rechecked, and how to maximise your chances of passing second time around.
You're entitled to a free partial retest if:
If you had dangerous or major defects, you can still get a free full retest within 10 working days, but more of the vehicle will be rechecked.
Working days = Monday to Friday only, excluding:
Example timeline:
After the 10-day window expires:
Pro tip: Book your retest a day or two before the deadline to avoid last-minute issues. If the garage is fully booked on day 10, you'll miss the free retest window.
There are two types of free retests, depending on what failed originally.
Who qualifies:
What gets checked:
Example scenario: Your car failed for:
On retest, the tester will check:
Who qualifies:
What gets checked:
Example scenario: Your car failed for:
On retest, the tester will check:
Why the difference? Dangerous and major defects often indicate neglect or underlying issues. A full retest ensures the vehicle is genuinely roadworthy, not just patched up.
Here's what typically gets rechecked based on the original failure:
| Original Failure | What Gets Rechecked on Partial Retest |
|---|---|
| Brake pads/discs | All brake components, brake fluid, handbrake, ABS (if fitted) |
| Tyre tread depth | All four tyres (tread depth, sidewalls, pressure, condition) |
| Headlight aim | All lights (headlights, sidelights, brake lights, indicators) |
| Emissions failure | Emissions, exhaust system, catalytic converter, oxygen sensors |
| Suspension bushings | All suspension components, steering, wheel bearings |
| Windscreen chip | Entire windscreen, mirrors, wipers, washer system |
| Number plate | Number plate legibility, security, font, spacing |
| Horn | Horn only (unless electrical work done, then all electrical items) |
Important: Testers have discretion to check related systems. If you replaced a headlight bulb, they might recheck all lights to ensure none are affected.
For a free retest: NO
For a paid retest: YES
The original garage issued the failure certificate and knows exactly what failed. They're responsible for confirming the repairs meet MOT standards. Going elsewhere would require a completely new test.
Exception: If you're unhappy with the original garage (e.g., you suspect they failed you unfairly), you can:
Don't cut corners:
Why? Testers will scrutinise repaired items closely. A poorly fitted brake pad or cheap tyre might fail again, even if it technically meets the standard.
Bring proof of repairs:
Why? If the tester queries a repair, you can demonstrate it was done professionally. This is especially useful for emissions work or electrical repairs.
Don't assume only the failed item will be checked:
Make it easy for the tester:
Why? A clean vehicle signals you've taken the retest seriously. A filthy underside might mean the tester can't properly inspect suspension components, leading to another failure.
| Scenario | Cost | What Happens |
|---|---|---|
| Retest within 10 working days at same garage | £0 (free) | Partial or full retest (VT20/VT30) |
| Retest after 10 working days | £54.85 (cars) | Full MOT test from scratch |
| Retest at different garage | £54.85 (cars) | Full MOT test from scratch |
| Appeal successful (DVSA overturn) | £0 (refunded) | You get original MOT fee back |
| Appeal unsuccessful | £54.85 (lost) | You pay for the appeal test |
Additional costs:
If you believe your vehicle was failed incorrectly, you can appeal to the DVSA (Driver and Vehicle Standards Agency).
Appeal if:
Common examples:
Success rate: Appeals are rarely successful unless there's clear evidence of tester error. Only appeal if you have strong grounds.
Problem: If the garage is fully booked, you'll miss the free retest window.
Solution: Book your retest 2-3 days before the deadline. This gives you a buffer for unexpected delays.
Problem: The 10-day rule states the vehicle shouldn't be driven except to/from the repair garage. Excessive mileage (e.g., 500 miles added) might disqualify you from a free retest.
Solution: Only drive to the repair garage and back to the MOT centre. Avoid long trips or daily commuting.
Problem: The original garage might refuse a free retest if they can't verify the repairs were done correctly.
Solution: Either:
Problem: Related items might fail on retest. For example, fixing a brake pad but ignoring a worn brake disc.
Solution: Ask your mechanic to check all related components, not just the failed item.
Problem: Partial retests can still take 30-45 minutes if multiple related systems need checking.
Solution: Book a retest appointment with enough time – don't expect a 5-minute check.
If you fail your retest (even within the 10-day window), you'll need to:
Important: The 10-day clock starts from the original test date, not from each retest attempt.
Example:
Your VT30 failure certificate lists every defect. Use it as a checklist:
Before returning to the MOT centre:
Why? Emissions tests require the engine to run at specific RPMs. Low fuel can cause:
How much? At least half a tank for petrol, quarter tank for diesel.
Drive for 15-20 minutes before the retest:
Pro tip: Don't turn off the engine when you arrive – let it idle for a minute or two before the test starts.
No. Advisories are not failures – they're items that "may affect vehicle safety or the environment if not repaired soon." You can't fail an MOT solely on advisories, so there's no retest to claim.
However, if an advisory item has worsened since the original test and now counts as a failure, you'll need to repair it before passing.
The tester has the final say on whether a repair meets MOT standards. If they believe your new brake pads are incorrectly fitted, they can fail the vehicle again.
Options:
Yes, but:
Common DIY repairs that work:
Repairs best left to professionals:
Yes. The 10 working day free retest rule applies to:
The only difference is the full MOT fee if you miss the window (e.g., £29.65 for motorcycles, £58.60 for Class 7 vehicles).
No. You cannot tax a vehicle without a valid MOT certificate (unless the vehicle is exempt).
Exception: If your MOT expires while you're waiting for a retest, you can drive to the retest appointment without tax only if you have a pre-booked MOT appointment.
Safest option: Get the retest done before your MOT expires, so you can tax the vehicle as soon as it passes.
✅ Return to the same garage within 10 working days (Monday-Friday only)
✅ Get repairs done properly – don't cut corners
✅ Check related items – the tester will inspect more than just the failed component
✅ Keep repair receipts as proof of work done
✅ Clean your vehicle – make it easy for the tester to inspect
✅ Warm up the engine before the retest (especially for emissions)
✅ Fill up the fuel tank – at least half full for petrol, quarter for diesel
✅ Book early – don't wait until day 10 in case the garage is busy
✅ Check all lights, tyres, and fluids yourself before returning
✅ Know your retest type – partial (VT20) or full (VT30)
Once you pass your retest:
Important: Your new MOT expiry date is 12 months from the original test, not from the retest. So if you:
This is why it's beneficial to get retested quickly – you don't lose any time from your MOT validity period.
The free retest system is designed to give you a fair chance to fix defects without paying twice. Use it wisely, get quality repairs, and you'll have a valid MOT certificate within days – without breaking the bank.
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