Short answer: weekly for surfaces at eye level and below, monthly for high surfaces, quarterly for the things nobody looks at.
By surface
| Surface | Frequency |
|---|---|
| Coffee tables, side tables, desks | Weekly |
| Shelves at eye level | Weekly |
| Windowsills | Weekly |
| Skirting boards | Monthly |
| Picture frames and wall art | Monthly |
| Light fittings and lampshades | Monthly |
| Ceiling fan blades | Monthly in summer |
| Tops of wardrobes, doors, cupboards | Quarterly |
| Curtains and blinds | Quarterly |
| Behind and under furniture | Quarterly |
| Vents and extractor covers | Quarterly |
Bedrooms need more than people expect. Most household dust is skin cells and textile fibres, and bedrooms generate the most of both.
Top down, then vacuum
Dust falls. Working top down means you only handle each surface once, ceiling fans, then high shelves, then furniture, then skirtings, then the floor.
Vacuum last, always. Dusting after vacuuming means everything you dislodge lands on carpet you just did.
Damp beats dry
A dry cloth or feather duster mostly moves dust into the air, where it settles again within the hour. A slightly damp microfibre cloth traps it. That single change does more than any product.
Microfibre also works on plain water for most surfaces. Polish and spray are largely unnecessary, and on timber, silicone-based polishes build up a film that attracts dust faster over time, so you end up dusting more.
If someone has allergies
Weekly minimum everywhere, and damp cloth only, never dry.
The things that matter most are not the visible surfaces: mattresses and bedding, curtains, upholstery and carpet edges hold far more than a coffee table does. Wash bedding weekly at 60°C where the fabric allows, vacuum the mattress every few months, and use a sealed HEPA vacuum so fine particles are captured rather than redistributed.
Airflow helps more than people expect. Opening windows for ten minutes a day moves a surprising amount of airborne dust out of a house, worth knowing in a New Zealand winter when everything stays shut.
If you are paying for it
Weekly-frequency dusting of reachable surfaces should be standard in any regular clean. The monthly and quarterly items, skirtings washed rather than wiped, light fittings, tops of things, behind furniture, are normally deep clean scope.
Worth asking your cleaner which list they are working from, because "dusting" without a defined scope is exactly where expectations diverge.