Yes, cranberries are safe for cats to eat in moderation — but only the unsweetened kind.
Cranberries have a number health benefits for cats, thanks to their high levels of vitamins A, B1, B2, C and E. They also have antioxidants, which can help boost your cat's immune system while reducing inflammation throughout their body. Cranberries may even help prevent urinary tract infections (UTIs) by preventing harmful bacteria from sticking to the walls of your cat's bladder.
With all that said, your feline friend should never eat commercial cranberry products that are packed with sugars or artificial sweeteners, as these are extremely unhealthy for cats. So while it may be safe to feed your cat plain fresh or dried cranberries, cranberry-based products like sweetened juice or muffins are off the menu.
If you do feed your cat plain cranberries, you should only do so in small quantities, as a very occasional snack. And keep in mind, cats are obligate carnivores, which means they need to get most of their nutrients from meat-based foods. Plant-based foods should never displace the meat in their diet.
As always, before introducing a new food item into your pet's diet, consult with your veterinarian first! If your cat eats cranberries (or any food) and is showing signs of illness such as lethargy, diarrhea, or vomiting, reach out to your veterinarian immediately. If your pet requires veterinary care due to something they ate, pet insurance can help cover the cost of treatment.