Using an artefactual field experiment, we elicit revealed preferences for solidarity of different age groups toward the same and other age groups among a large, diverse Dutch population sample. Preferences are measured with a solidarity game and linked to a unique administrative database, allowing exploration of demographic and socio-economic correlates. In the game, a winner of a money amount is asked ex-ante how much they are willing to transfer to a loser who gets nothing. Participants, on average, show a strong preference for ex-ante solidarity, willing to transfer about 40% of the money. However, participants are overly pessimistic about what others will transfer. We also observe age-based discrimination, as many show stronger solidarity with their own age group. Using questionnaires, we measure stated preferences in various domains and find revealed preferences correlate with some self-reported attitudes and with opinions on social security and solidarity-related field behavior.