Yes, an employer can decrease your salary but subject to certain criteria. An employer is not at liberty to unilaterally change the terms and conditions of employment, the employer must consult with the employee on the proposed changes and a mutual agreement should be reached.
In Plaatjies vs RK Agencies (2005, 1 BALR 77) the employer offered the employee an alternative post at a lower salary due to the fact that the employer had lost a major contract. While the arbitrator accepted this as a valid reason the demotion was still unfair because the employer had failed to consult with the employee before making the offer.
Further to the above, if an employee has been demoted through a lawful process, this will include disciplinary action against an employee, once accepted the employer is under no obligation to keep the employee on the higher salary.
In Sass vs African Life Assurance (2005, 6 BALR 682) the employer demoted the employee for failing to make sufficient sales. The CCMA found this to be unfair as the employer had proved neither that the performance had been bad nor that it had followed legal procedure before implementing the demotion. The employer was ordered to reinstate the employee in the higher position.
In a nutshell, the employer cannot decrease your salary at liberty! You must agree!
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