Drone Weight Limits in the UK: Categories Explained

Why Weight Matters

The weight of your drone determines which category it falls into, what qualifications you need, whether you must register it, and what insurance is required. Heavier drones pose greater risks to people and property in the event of a malfunction or collision, so the regulatory framework applies progressively stricter requirements as weight increases.

Weight in this context means the Maximum Take-Off Mass (MTOM), which includes the drone itself plus its battery, any payload (such as a camera), and any accessories attached at the time of flight.

Sub-250g Drones

Drones with a MTOM of less than 250 grams enjoy the lightest regulatory burden. Key rules for this category:

• Registration: You must obtain an Operator ID and a Flyer ID through the CAA registration service, even for sub-250g drones that are equipped with a camera
• Subcategory: Sub-250g drones that are class-marked C0 (or those in the transition period without class marking but under 250g) can fly in subcategory A1, which permits flight over uninvolved people (though not over crowds)
• Insurance: Not legally required for non-commercial flights, though recommended
• Qualifications: You must pass the free online theory test to obtain your Flyer ID

Popular sub-250g drones include the DJI Mini 4 Pro and DJI Mini 3. Despite their lighter regulation, all standard rules regarding altitude (120m), no-fly zones, and responsible flying still apply.

250g to 25kg: The Open Category

Drones weighing between 250g and 25kg operate in the Open category, divided into three subcategories based on weight and intended operation:

Subcategory A1 (under 900g with C1 class marking)

Drones with a C1 class marking and MTOM under 900g may fly in subcategory A1. This permits flight near (but not intentionally over) uninvolved people. The pilot must hold a valid Flyer ID.

Subcategory A2 (under 4kg with C2 class marking)

C2-marked drones under 4kg can fly in subcategory A2, which allows operations closer to uninvolved people (a minimum of 30 metres horizontally, reducible to 5 metres in low-speed mode). The pilot must hold an A2 Certificate of Competency (A2 CofC) in addition to the Flyer ID.

Subcategory A3 (under 25kg with C3 or C4 class marking)

Drones up to 25kg with C3 or C4 class markings operate in subcategory A3. These must be flown in areas where it is reasonably expected that no uninvolved person will be endangered, and at a safe distance of at least 150 metres from residential, commercial, industrial, or recreational areas.

Transitional Provisions

Many drones currently on the market do not carry a C0-C4 class marking because they were manufactured before the class marking system came into effect. Under the current transitional provisions (extended in the UK), these legacy drones can still be flown in the Open category, subject to specific conditions:

• Legacy drones under 250g: treated similarly to C0 in subcategory A1
• Legacy drones 250g to under 500g: can fly in A1 (with limitations) during the transition period
• Legacy drones 500g to 25kg: must fly in A3 (150m from populated areas)

Check the CAA website for the most current transition period end dates, as these are subject to regulatory updates.

Over 25kg: Specific and Certified Categories

Drones with a MTOM exceeding 25kg cannot operate in the Open category. They require either:

• Specific category: Requires an Operational Authorisation from the CAA, based on a risk assessment. The pilot must hold appropriate qualifications (typically a GVC or higher).
• Certified category: For the highest-risk operations, similar to manned aviation certification. This includes type certification, operator certification, and pilot licensing.

Insurance is mandatory for all Specific and Certified category operations, with minimum coverage as specified by the CAA.