Parts for your 2020 Mazda 3-Cabin filter

2020 Mazda 3 cabin filter — what it does and when to replace it

Technical sources confirm the 2020 Mazda 3 (BP series) is fitted with a serviceable cabin air filter. The 2020 Mazda 3 Owner’s Manual (BP) lists an “Air filter (A/C)” within the maintenance schedule, the Mazda Workshop Manual includes an “Air Filter Removal/Installation” procedure located behind the glovebox for BP models, and Mazda’s electronic parts catalog for BP-series Mazda 3 (2019–on) lists a dedicated cabin/pollen filter element for the HVAC unit. So yes — this model absolutely uses a cabin filter.

In the 2020 Mazda 3, the cabin filter’s job is simple but important: it cleans the air that comes through the heater and A/C so the cabin stays fresher. It traps dust, pollen, soot, and road grime, an activated carbon version also helps knock out whiffs of diesel, exhaust, and bushfire smoke that can creep into traffic. That means clearer sinuses for allergy sufferers and less haze on the windscreen from oily particles.

As part of routine servicing, it’s smart to inspect the cabin filter at every service and replace it regularly. Mazda’s schedule typically calls for replacement about every 24 months or 40,000 km, but Aussie and Kiwi conditions can be tougher — unsealed roads, coastal salt air, heavy urban smog, or a big pollen season can clog the media quicker. If the car spends time in dust or smoke, plan on 12–18 months (or 15,000–30,000 km). Activated carbon filters are a top pick for city commuters or anyone sensitive to odours.

There are tell-tale signs when the 2020 Mazda 3 wants a fresh filter:

• Fan feels weak at the same speed
• Musty or exhausty smells on fresh-air mode
• Windscreen fogs up more easily
• Visible contamination on the filter media

The filter sits behind the glovebox. Many DIYers handle it themselves: drop the glovebox, pop the access cover, slide the old filter out, and install a new one with the airflow arrow pointing the right way. If the car has been through a dusty spell, a quick vacuum of the housing (carefully, without damaging the evaporator fins) helps. Otherwise, ask an authorised Mazda technician to check and replace it during scheduled servicing — they’ll reset reminders and make sure the HVAC drain and seals are all good.

Bottom line: keeping the 2020 Mazda 3’s cabin filter fresh makes the A/C work easier, the air nicer to breathe, and the drive that little bit more relaxed.

FAQs

Where is the cabin filter in a 2020 Mazda 3 and how long does it take to change?
It’s located behind the glovebox. Release the glovebox stops, lower it, remove the rectangular access cover on the HVAC unit, then slide the filter out and in. Most people can swap it in 10–20 minutes with basic care.

If unsure, a workshop can do it during a regular service and check the evaporator area and drain at the same time.

How often should it be replaced in Australia or New Zealand?
As a rule of thumb, every 24 months or around 40,000 km works well. In dusty regions, after bushfire smoke exposure, or with lots of urban stop‑start driving, aim for 12–18 months (15,000–30,000 km). Inspect it at each service and replace sooner if airflow drops or odours appear.

Should the 2020 Mazda 3 use a standard pollen filter or an activated carbon filter?
Both fit. A standard pollen filter is great for dust and allergens and is budget‑friendly. An activated carbon filter is ideal in cities or for sensitive noses, as it helps reduce odours and some gases. Many owners prefer carbon for year‑round comfort.