Every Slowking card we price, most valuable first. Prices are what copies actually sold for, updated daily.
The same Pokemon is also printed as Galarian Slowking, priced separately because the game treats them as different cards.
What a Slowking card is worth
The most valuable Slowking on this list is Slowking (H22) from Aquapolis at $374.45£281.83€329.77, and the 22 priced copies across 18 sets are worth $1.4k£1.1k€1.3k together. Most of that sits in a handful of printings: the older the set and the scarcer the print run, the wider the gap to the rest.
Slowking is printed in Japanese as well: 18 cards across 16 sets, the most valuable of them Slowking from Wind from the Sea at $262.50£197.57€231.18. Switch the list above to Japanese to read those, or to Both to rank the two catalogues against each other.
The highest PSA 10 on record for Slowking sold for $68,053£51,220€59,933. 1st Edition and reverse holo printings are priced separately from the standard card, because they do not trade at the same money.
If you are trying to identify which Slowking you have, the set name is printed on the card and the collector number sits in the bottom corner. Open the card here and the page carries every printing of it, the graded prices, and whether grading the copy is worth the fee. Sets to start with: Aquapolis, Southern Islands, Neo Genesis.