Sippy cups are generally considered to be quite durable in nature, however, it does depend on how often you use them. That means, if you are using these cups once in a while they might last longer, but, if they are used regularly, they must be replaced each month or within two.Also, as we know these notorious and curious kids are at times too hard on them and might just end up with a scratch or a crack here and there. So, the golden rule is, if, in a good position, you might as well have earned yourself a durable fortune.