Why do I need a Certificate of Fitness (CoF)?

AutoTrader NZ
Published 15 April 2024

A Certificate of Fitness (CoF) in New Zealand is a critical aspect of vehicle compliance and safety, often less understood than the Warrant of Fitness (WoF). This comprehensive guide aims to enhance your understanding of a CoF, compare it with a WoF, and explain why it is essential for specific vehicles and their operators.

It’s important to understand the distinction between a Certificate of Fitness (CoF) and a Warrant of Fitness (WoF), as both serve pivotal roles in ensuring vehicle safety and compliance.

Understanding the Certificate of Fitness (CoF) and Warrant of Fitness (WoF)

What is a Certificate of Fitness (CoF)?

A CoF is a stringent inspection designed to assess the structural integrity, safety features, and mechanical reliability of vehicles, primarily due to their extensive use and the higher demands placed on them. Vehicles requiring a CoF include:

  • Vehicles over 3500kgs Gross Vehicle Mass (GVM)
  • Commercial vehicles
  • Rental vehicles, including cars, campervans, and motorhomes
  • Public service vehicles, such as taxis and buses

CoF-A: all light passenger service vehicles e.g. taxis and rental vehicles that are all under 3500kgs. (This is a similar check to a WoF)

CoF-B: all heavy vehicles e.g. vehicles over 3.5 tonnes.

What is a Warrant of Fitness (WoF)?

A WoF is mandatory for personal and light commercial vehicles, focusing on critical safety components like brakes, tires, lights, and seat belts to ensure they function correctly and safely.

Key Differences Between CoF and WoF

  • Purpose and Vehicle Type: The CoF targets commercial and heavier vehicles, necessitating a more thorough inspection to address their increased use and potential safety risks. Conversely, the WoF caters to personal and lighter commercial vehicles, emphasizing essential safety features.
  • Inspection Rigor: CoF inspections are more comprehensive, reflecting the higher safety standards required for vehicles under heavier use.

Cost of a CoF at VINZ in New Zealand

  • From $85 for vehicles under 3500kgs GVM (CoF-A)
  • From $231 for vehicles over 3500kgs GVM (CoF-B)
*Note: Prices are indicative only

What’s included in the CoF check at VINZ?

Depending on the type of vehicle, some or all of the following are checked:

  • Brake performance and condition
  • Doors
  • Exhaust condition and performance
  • Fuel system condition
  • Glazing
  • Lighting performance and condition
  • Load anchorage systems
  • Mudguards and mud flaps
  • Occupant protection systems
  • Safety belts
  • Speedometer
  • Steering and suspension
  • Stock crate and crate retention system condition
  • Structural condition
  • Towing connections
  • Wheel and tyre condition
  • Windscreen washers and wipers

Common Issues When Failing a CoF

Successfully passing a CoF inspection often hinges on preemptive attention to common issues, including:

  • Tyre Maintenance: Inspectors check for proper condition, adequate tread depth, and correct inflation.
  • Structural Integrity: The vehicle’s chassis and body are examined for rust, corrosion, and structural damage.
  • Braking System: The inspection covers brake pads, fluid leaks, damaged lines, and overall performance.
  • Lighting: All vehicle lights must be operational, without burnt-out bulbs or faulty connections.
  • Steering System: The steering’s operation and alignment are critical, with failures often due to wear or misalignment.
  • Suspension System: The suspension is evaluated for wear and damage, affecting stability and safety.

The Importance of Compliance: Why You Need Them

  • Legal Compliance: Operating a vehicle without a current CoF or WoF can lead to fines, penalties, and impoundment.
  • Safety Assurance: These inspections help identify and address potential safety hazards, ensuring the safety of drivers, passengers, and the public.
  • Maintenance and Vehicle Value: Regular inspections promote ongoing maintenance, extending the vehicle’s lifespan and preserving its value.


Distinguishing between a Certificate of Fitness (CoF) and a Warrant of Fitness (WoF) is crucial for anyone involved with vehicles in New Zealand. Understanding these requirements ensures legal compliance, promotes safety, and contributes to a responsible driving environment. This guide aims to clarify the CoF process, underscoring its importance for specific vehicle types and the benefits of adherence to these standards.

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