Drone Altitude Limits Compared: UK and Beyond

The 120-Metre Standard

The 120-metre (approximately 400-foot) altitude limit has become the de facto international standard for drone operations in the Open category. This limit was established to keep recreational and basic commercial drones well below the altitudes used by manned aircraft in most airspace classes. The International Civil Aviation Organization (ICAO) has endorsed this threshold in its guidance documents, and most national regulators have adopted it.

United Kingdom

The UK CAA enforces a 120-metre maximum altitude above ground level for all drone operations in the Open category. This limit applies regardless of the drone's weight class or the pilot's qualifications within the Open category. Operations above 120 metres require Operational Authorisation under the Specific category, with appropriate risk assessment and safety measures.

The UK permits flights above 120 metres in certain circumstances when operating within 50 metres of a structure taller than 120 metres, provided the drone remains within 50 metres of the structure at all times. This exception allows for building inspections and similar close-proximity work on tall structures.

European Union (EASA Member States)

EASA regulations set a 120-metre maximum altitude above ground level for Open category operations across all member states. This limit is consistent with the UK's, reflecting their shared regulatory heritage. Individual member states may designate geographic zones where lower altitude limits apply (such as near airports or military installations), but they cannot raise the default limit above 120 metres for Open category operations.

The same tall-structure exception applies under EASA rules, allowing operations above 120 metres when within 15 metres of a structure that exceeds the altitude limit, subject to the structure owner's permission.

United States

The FAA sets a maximum altitude of 400 feet (approximately 122 metres) above ground level for drone operations under Part 107 (commercial) and recreational rules. The slight difference from the 120-metre metric standard reflects the USA's use of imperial measurements in aviation.

The FAA permits operations above 400 feet when within a 400-foot radius of a structure, provided the drone does not exceed 400 feet above the structure's highest point. This exception is more generous than the UK's 50-metre proximity requirement, allowing a wider working area around tall buildings.

Australia

CASA enforces a 120-metre maximum altitude above ground level for standard drone operations. Australia's vast and varied terrain means that this limit applies across environments ranging from dense urban areas to remote outback locations. There are no general exceptions for operations near tall structures under standard recreational or commercial rules — above-120-metre operations require specific CASA approval.

Canada

Transport Canada sets a maximum altitude of 122 metres (400 feet) above ground level for drone operations under both Basic and Advanced pilot certificates. Canada does not provide a general tall-structure exception in its standard operating rules. Operations above 122 metres require a Special Flight Operations Certificate (SFOC) from Transport Canada.

New Zealand

CAA NZ sets a maximum altitude of 120 metres above ground level under Part 101. Operations above this limit are possible under Part 102 with appropriate certification and risk assessment. New Zealand's mountainous terrain means that understanding altitude measurement (above ground level vs above mean sea level) is particularly important for operators in highland areas.

Measurement Considerations

All jurisdictions discussed here measure altitude above ground level (AGL), not above mean sea level (AMSL). This distinction is crucial in hilly or mountainous terrain, where ground level changes continuously. A drone flying at 120 metres AGL on a hillside may be at a substantially different AMSL altitude than one flying at 120 metres AGL in a valley.

Most consumer drones measure altitude using a barometric sensor calibrated at the take-off point. This means the altitude reading represents height above the launch site, which approximates AGL only when flying over relatively flat terrain near the launch point.

Obtaining Higher Altitude Permissions

All jurisdictions provide pathways for operating above the default altitude limit. These typically require:

• A formal application or risk assessment submitted to the national aviation authority
• Demonstrated operational need (such as infrastructure inspection)
• Enhanced safety measures, which may include transponders or observers
• Coordination with air traffic control in controlled airspace