What an advisory is
An MOT advisory is a fault that passed this time but is wearing out. It isn't a fail, but it's work to plan, and a buyer should price it in.
Since 20 May 2018, MOT defects fall into four groups. Dangerous and major defects are fails, and a dangerous one means the car must not be driven. Minor defects pass and are recorded. Advisories pass too, but they warn you that a part is on its way out.
The advisories you'll see most are tyres worn close to the legal limit, brake discs worn or pitted, tyres cracking or perishing, and brake pads wearing thin. Tyres need at least 1.6mm of tread across the central three-quarters, and brake pads fail below 1.5mm, so an advisory on tyres or pads means the work is getting close.
Check the MOT history before you buy and look for repeats. An advisory that appears test after test with no work done is a bill waiting to arrive. Get a quote for the parts and labour, and take that off your offer.
The most common advisories
Most advisories are about wear. They passed this time, but each one is repair work you'll probably pay for soon, so price it in before you agree a figure. The ones you'll see most are worn tyres, worn brake discs and pads, and perished tyres.
Tyres near the legal limit mean the tread is close to the 1.6mm minimum across the central three-quarters. Tyres cracking or perishing is different: the rubber has aged, so a tyre can fail even with good tread.
Brake pads wearing thin means they're getting close to failing, and pads fail below 1.5mm. Brake discs worn or pitted means the surface is rough or thinning, and worn discs often go with worn pads. Corrosion means rust that hasn't yet caused a fail, on parts such as brake pipes or the underside, and it can get worse quickly. Our free MOT history check shows the advisories from each past test, so you can see if one keeps coming back.
Advisories when buying a car
Read the last MOT's advisories before you agree a price. An advisory means the car passed, but a part is wearing out and will need work soon. A free MOT history check shows the advisories from each test, so you don't have to rely on the seller's word.
Look for advisories that keep coming back. If the same one appears on several MOTs, nobody has fixed it. The most common are tyres worn close to the 1.6mm legal minimum, brake discs worn or pitted, tyres cracking or perishing, and brake pads wearing thin. Pads fail below 1.5mm.
Use them to negotiate, or ask what's been done. Ask the seller for receipts for any work listed. If nothing has been done, get a garage quote and take that cost off your offer. Don't hand over money until you've checked the history.