The rule is that you are socially insured in the country where your employer is registered. This is only different if you also work for at least 25% of the time in your home country, should this be a different country, then you are socially insured in your home country. Exemption from Dutch social premiums, it is possible.
If you work in the Netherlands for a short period, max two years, then you can ask the other EU country to issue a so called A1 statement, previously known as E101 statement. With this statement you are no subject to Dutch social premiums.
To give you an idea of the impact. The income tax rate over the first EUR 19.645 you earn is subject to 36,25 income tax. If you are not socially insured here, the tax rate drops to only 5,1%. The next bracket taxes the income from EUR 19.646 to EUR 33.363 and the tax rate is 42%. If you are not socially insured here, the tax rate drops to only 10,85%. Moreover, you are not obliged to take out a Dutch health care insurance.
The A1 statement makes you exempt from social premiums
Even if the A1 statement or E101 statement is issued based on incorrect information, or applies to a different situation, then the Dutch authorities are obliged to honor this statement.
Please realize that in your home country you are due the social premiums amount applicable there over the income generated in the Netherlands. That implies you cannot spend your full Dutch net salary ,as you need a significant amount in your home country for the premiums to be paid.
Moreover, before you apply for this statement, check if our social premium rates are indeed higher than in your home country. This is not always the case.
The down side is that you also cannot benefit from our social system. No pregnancy leave, no unemployment, disability. Hospital assistance will be less easy.