If you've bought a drone in the last twelve months, you'll have noticed a small printed label on the airframe — a C followed by a number from 0 to 6. That class identifier (CI) is now one of the most consequential things about the drone, because it dictates where you can fly it under the Open category, and what your operator needs to do to fly it in Specific.
Here's a plain-English summary of what each class means in 2026.
The class system in one paragraph
Class identifiers (originally an EU concept, adopted by the UK) sort drones into bands based on weight, energy and other safety characteristics. Manufacturers self-declare conformity, and the label is a manufactured-in marking like a CE mark — you don't apply for it, the airframe ships with it. Class identifiers don't replace the operational categories (Open / Specific / Certified) — they cross-reference with them to determine what you can do.
The classes, in order
| Class | Max takeoff weight | What it’s for |
|---|---|---|
| C0 | < 250 g | Toy and hobby-grade. Can be flown in Open A1, including over uninvolved people. |
| C1 | < 900 g | Sub-1 kg consumer/prosumer. Open A1 — close to but not over uninvolved people. |
| C2 | < 4 kg | Prosumer/light commercial. Open A2 if pilot has A2 CofC — 30 m / 5 m horizontal stand-off with low-speed mode. |
| C3 | < 25 kg | Larger commercial. Open A3 only — uninvolved people 150 m+ away. Or Specific Category with OA. |
| C4 | < 25 kg | Model-aircraft style, no auto modes. Open A3 only. |
| C5 | < 25 kg | Modification kit for C3-class. Enables PDRA-S01 Specific Category ops. |
| C6 | < 25 kg | Designed for BVLOS operations under PDRA-S02. Limited models on market in 2026. |
Why this matters for surveys
The class label determines whether you can fly Open A2 (close to uninvolved people) or are forced into Open A3 (150 m horizontal stand-off — which makes most urban roof surveys impossible) or Specific Category (which needs an OA).
A practical example: a typical Mavic 3-class drone, around 900 g, that ships C2-marked, lets a pilot with an A2 CofC fly with a 5 m horizontal stand-off in low-speed mode. The same airframe shipped without a class label — or marked C3 — would force a 150 m stand-off, which closes off urban work entirely in the Open category.
Legacy “unmarked” drones
Drones bought before class labelling became mandatory in the UK are now “legacy”. The transition rules:
- Unmarked sub-250 g drones can still be flown in Open A1 as if they were C0.
- Unmarked drones between 250 g and 25 kg can only be flown in Open A3 — 150 m from uninvolved people, no flying over residential, commercial, industrial or recreational areas. Or under a Specific Category OA.
For working operators, this effectively means: if your drone is unmarked, your urban survey work happens under a Specific Category OA — there’s no Open-category back door.
What clients should check
If you’re hiring a drone operator and your site is in a town, ask which class their airframe is marked, and which operational category they’re flying under. C2 + A2 CofC + reasonable stand-off, or any class operating under a Specific Category OA — both are fine. C3 unmarked + no OA + flying near your house — that’s not.