The cost of CompEx varies depending on whether you attend a formal training course before the assessment, which units you are taking, and which assessment centre you use. This guide gives a realistic overview of what to budget for CompEx in 2025.
CompEx Assessment Fees
The formal CompEx assessment fee (covering the written and practical assessment) varies between assessment centres but typically falls in the range of £500–£800 per unit. Many candidates take multiple units simultaneously (e.g. Ex01 and Ex03 together), which can reduce the overall cost.
Training Course Costs
Most candidates attend a formal CompEx preparation course before their assessment. These courses typically run for 5–7 days and are offered by a range of training providers across the UK. Course fees typically range from £1,200–£2,000 per candidate depending on the provider, location, and number of units covered.
Total Cost
Including preparation course and assessment fees, candidates typically budget £1,700–£2,800 for a CompEx Ex01/Ex03 combination. For Ex02/Ex04 additions the cost increases accordingly.
Online Preparation — A Cost-Effective Alternative
Online preparation platforms like EX Academy offer a significantly more cost-effective way to build the knowledge foundation before attending a formal course or assessment. At £19.99/month, you can work through all 15 inspection simulations, 15 equipment selection scenarios, 14 training modules, and 1,185+ practice questions — putting yourself in a much stronger position before your formal assessment course and reducing the risk of a costly resit.
Many employers in the oil and gas, offshore, and petrochemical sectors fund CompEx assessments for their electricians as part of their ATEX/DSEAR compliance obligations. If your employer requires CompEx, they should be covering the assessment cost — and may also fund preparation courses. Online preparation is often self-funded as a cost-effective supplement.