Whether or not an individual is a tax resident of the Netherlands is determined by weighing all the facts and circumstances. If you live in the Netherlands (with your family) and mostly work in the Netherlands for a Dutch based employer you probably are a resident taxpayer.
Dutch income tax is levied on three categories (“Boxes”) of income. Each Box has its own rules for the calculation of taxable income, has its own tax rates, exemptions, credits, etc. A resident taxpayer is subject to Dutch income tax for his/her world-wide income and is taxable in the Netherlands on income in all three boxes.
Box 1 consists - among other things - out of employment income and income from a primary residence (the house you live in). Dutch wage tax (together with Dutch social security premiums) is levied throughout the year (pay-as-you-earn) on employment income. The Dutch wage tax is an advance payment of the final Dutch income tax payable. If too much wage tax is withheld (common in immigration or migration years) you can get an income tax refund by filing a personal income tax return. If too little wage tax has been withheld throughout the year (this sometimes happens when you change employers during the year or receive high bonuses or salary raises) it's possible that you have to pay income tax after filing your personal income tax return.
Box 2 consists out of of income from a substantial shareholding (at least 5% of a certain class of shares).
Box 3 consists out of income from savings and investments. One of the extra benefits of the 30% tax ruling is that a resident taxpayer can choose – via his/her Dutch personal income tax return - to be treated as a partial non-resident taxpayer for Dutch tax purposes. A partial non-resident taxpayer is subject to Dutch income tax as a resident taxpayer for Box 1 income and as a non-resident taxpayer for Box 2 and Box 3 income.