This will take €20,900 off his annual €292,000 salary.
His son Crown Prince Felipe is set to lose €10,450 euros – putting him on a salary of €131,000.
In total, the royal household aims to save €100,000 on wages as other members of the family, including Queen Sofia and Felipe's wife Letizia, are affected too.
The changes come after protests over austerity measures that will mean Spanish civil servants lose their Christmas bonuses, equivalent to seven percent of salaries.
It also follows the unprecented move last year to disclose the monarch's earnings.
In the wake of a corruption case centering on the business dealings of his son-in-law Iñaki Urdangardin, the king was keen to project an image of transparency.
The family has had a difficult few months. Earlier this year the royal patriarch had to be flown back to Spain for an emergency hip operation after falling on a hunting trip to Botswana.
His 13-year-old grandson Felipe Juan Froilan also shot himself in the foot accidentally while handling a gun.