If you want to change employer it may be possible to apply for the 30% ruling with your new employer. This depends on whether you have the 30% ruling already or not.
Important is that the gap between the last work day at your previous employer and the date of arranging an employment contract with your new employer is not longer than 3 months. This period is very rigid. The tax authorities assume that if it takes you more than 3 months to find a new job, that you no longer have the unique skills and experience which are scarce in the Netherlands. Consequence is that the 30% ruling is no longer applicable, not even if the salary you will receive is higher than the required amount.
There have been many court cases about the 3 months period. The Courts have ruled that this 3 month period is a fixed period. It can't be extended. Nor can it be put on hold because the employee has decided not to search for work due to other reasons (like finding a home, following a study or taking a sabbatical leave). Not searching for a job doesn't lead to the assumption that there is still scarcity unless proven otherwise. The advice therefor is, is to find a job within this three months even if you won't be available for work yet during these three months. The legislation focuses on the date an employemt contract is agreed and not on the actual start date of the employment.
So if you have the 30% ruling with your current employer and you want to change employer, it is possible to get the ruling with your new employer. If you don’t have the 30% ruling with your current employer then it is important to know why you don’t have it now. If you qualified for the ruling but due to company policies your employer didn’t want to apply or just forget to apply, you can still get it with your employer. The maximum term of the ruling will however be reduced with the period you worked for your current employer though.
But if you didn’t qualify for the 30% ruling when you applied with your current employer and you change employer, you won’t get the ruling with your new employer either. Not even if you would have qualified now. Relevant is the situation the day you started working in the Netherlands. You would then only make a chance if you would leave the Netherlands and find a job here later and come back again.
If you change employer Expatax can help you to determine whether you will qualify for the 30% ruling with your new employer and assist you and your new employer with the application.