Home-delivery customers of Poland Spring water have filed a putative class action in federal court, claiming the bottler imposes late fees that are fraudulent, usurious and violate contract terms.

The late fees, amounting to $15 to $20 a month, are charged even when customers pay on time and without regard to the amount due, so they can exceed 75 percent of a customer’s bill, says the suit, Ciser v. Nestle Waters North America Inc , filed Wednesday in Newark.