You have received a letter with a positive decision on your application for naturalisation or option. This letter does not yet mean that you are immediately a Dutch citizen. You can read here what still has to happen before you are a Dutch citizen.
According to the IND you meet all conditions to become a Dutch citizen. This decision will be forwarded to the King of the Netherlands. The King has to place his signature on the Royal Decree Dutch citizenship (Koninklijk besluit Nederlanderschap). By doing so he gives official permission to give you Dutch nationality.
The naturalisation ceremony is obligatory. You will become a Dutch citizen only if you go to the naturalisation ceremony. Municipalities organise naturalisation ceremonies. In this way, the municipality celebrates together with you that you have become a Dutch citizen. But during the naturalisation ceremony attention is also paid especially to the meaning of Dutch nationality.
You have to go to the naturalisation ceremony within 1 year after the decision. Will you not do so? Then you will not get Dutch nationality. And you have to apply for naturalisation again.
During the ceremony you will make a Declaration of Solidarity. By making the Declaration of Solidarity you declare that you know the laws of the Kingdom of the Netherlands also apply to you. Afterwards you will receive proof that you have become a Dutch citizen: the naturalisation decision or the option confirmation.
Was your child 16 years of age or older when the application for naturalisation was submitted? In that case you child is also required to attend the naturalisation ceremony. Is your child under 16 years of age? Then your child does not have to go to the ceremony, but may do so if they wish.
Did you go to the naturalisation ceremony? And have you received the naturalisation decision or the option confirmation? You can then apply to your municipality for a Dutch passport.
Did you have a foreigner's or refugee's passport? You must hand it in when you receive your Dutch passport.
Have you become a Dutch citizen? And have you stated with your application for naturalisation that you will renounce your other nationality? You must then renounce your other nationality. You can often do this at the embassy or consulate of that country in the Netherlands.
Was your child not naturalised together with you? After you yourself have become a Dutch citizen you can still apply for naturalisation for your child. This is called subsequent naturalisation.
Your child has lived in the Netherlands for at least 3 years without interruption.
Your child has a permanent residence permit or a temporary residence permit with a non-temporary purpose.
Your child lives in the Netherlands.
Your child has a valid residence permit for a non-temporary purpose, for example for residence with the parents.
Subsequent naturalisation of a child born during your procedure is free if you make the application within 1 year after you yourself became a Dutch citizen.