In 2022 the socioeconomic status (SES) scores have been published for general usage. The SES scores are available on the global drive of the Lifelines Workspace and can be directly linked to the data using postal codes (PC4) (sections: secondary & linked variables).
Every 2-4 years, Statistics Netherlands (CBS) and the Netherlands Institute for Social Research (SCP) publish status scores for each postal code within the Netherlands. Scores are based on the inhabitants’ average educational level, income and job prospective. Scores are mean-centered but not standardized across the country and range from approximately -8 to +3 (range differs slightly by year).
The socioeconomic status scores are available from 1998 up to 2016. More recent years aren't available as the score is no longer calculated by the SCP. In the future Statistics Netherlands will calculate status scores on a neighbourhood level. See also this update on their website (in Dutch).