Can I change the pollen filter myself, or should a garage do it?
Yes, most people can. A garage charges £30-70 to change a cabin pollen filter that costs £8-18, and on most cars it lives behind the glovebox and comes out in about fifteen minutes. Fiddly is the right word, not difficult. It's also the cheapest fix there is for musty-smelling air vents and hay fever misery in traffic.
What you'd pay a garage vs the filter price
| Garage, fitted | Filter only | You save |
|---|---|---|
| £30-70 | £8-18 | £22-52 |
The pollen filter (also called the cabin filter) cleans the air blowing through your vents, and it's a favourite service-time upsell precisely because most owners don't know where it is. £70 for a part costing a tenner and fifteen minutes of glovebox wrestling is a very healthy margin for somebody. It might as well be you who pockets it.
How hard is it really?
On most cars, the filter sits in a slot behind or below the glovebox. The usual routine: open the glovebox, squeeze its sides (or unhook a small strap or damper arm) so it swings all the way down, unclip a plastic cover, and slide the old filter out. It'll probably shower you with leaves and grime, which is oddly satisfying. Slide the new one in with the airflow arrow pointing the right way, usually printed on the frame, refit the cover, click the glovebox back. Fifteen minutes the first time, five the second.
Some cars put it under the bonnet instead, at the base of the windscreen behind a plastic panel. Still easy. The unlucky few have it up under the dash on the driver's side, where you're lying in the footwell working one-handed above your own face. Check a quick video for your model so you know which layout you've got before you buy anything. Once you know, the filter itself is £8-18 by registration; the activated carbon version costs £3-5 more and is worth it, because the carbon layer soaks up traffic fumes and smells, not just pollen.
Why bother? (The smelly vents fix)
Because this cheap, hidden filter causes a surprising amount of everyday grief. A clogged one makes the windscreen slow to demist, cuts how hard the fans blow, and holds damp debris that makes the whole car smell like a wet gym bag when the aircon starts. If you get sneezing fits in traffic every spring, a fresh carbon filter is the first thing to try. Most schedules say change it yearly or every 12,000-15,000 miles, and in practice hardly anyone does. If your car's more than a couple of years old and you've never seen it done on an invoice, it's due.
When you should NOT DIY this
Two situations. If your model turns out to be one of the awkward under-dash designs and you've got a bad back or big hands, the £30-70 is honestly fair; some of those are miserable. And if trim panels need more than gentle persuasion, stop rather than snap the clips, because brittle ten-year-old plastic breaks easily and a broken glovebox hinge costs more than the garage would have.
If you'd rather a garage do it
Fair is £30-70 on its own, and it should be near the bottom of that range done alongside other work. On a full service it's often included, so check your service checklist before paying a separate line for it, and don't pay for it twice a year when the schedule says once. A dealer quote of £90+ for a glovebox-access filter is having a laugh; compare what an independent would charge in our dealer vs independent guide.
Common questions
How often should a pollen filter be changed?
Once a year or every 12,000-15,000 miles is the common recommendation, ideally in spring before pollen season. If you drive mostly in town traffic, the carbon type clogs with soot faster. In reality most cars go years without one, which is why so many smell musty inside.
What's the difference between a pollen filter and an activated carbon one?
A standard pollen filter traps dust, pollen and debris. An activated carbon version adds a charcoal layer that also absorbs exhaust fumes and odours before they reach the cabin. It costs £3-5 more and it's the one to buy if you sit in traffic or notice smells through the vents.
Can a blocked pollen filter cause windows to steam up?
Yes, it's one of the most common causes. The filter chokes airflow through the heater, so less dry air reaches the glass and the windscreen takes ages to demist. If your blower seems weak on full and the windows fog easily in winter, check this filter before blaming the heater.
Does the pollen filter affect air conditioning?
It affects how well you feel the aircon. The system may chill air perfectly, but a clogged filter strangles the airflow carrying it to you, so the car cools slowly and the fans sound busier than they should. A damp, dirty filter is also the usual source of that musty aircon smell.
Will a dirty cabin filter fail the MOT?
No, the pollen filter isn't part of the MOT test at all. The tester never looks at it. That's partly why it gets neglected for years. The reasons to change it are comfort and health: clean air, working demist, decent fan flow and no musty smell, rather than any legal requirement.