This discussion clarifies the tax treatment of Employee Stock Option Plans (ESOPs) in the UK. It explains that the difference between the Fair Market Value (FMV) and the exercise price is taxed as salary at the time of exercise. Any subsequent capital gain upon selling the shares is calculated based on the sale price minus the FMV at the exercise date. While tax is typically due at exercise, there are deferral options for eligible start-ups, and employees may be able to claim a refund if excess tax has been deducted by their employer.