The charging time for rechargeable hearing aids varies depending on the specific model and the state of the battery. On average, most rechargeable hearing aids take 2-4 hours to fully charge. However, some high-end models with larger batteries may take longer. Many rechargeable hearing aids also feature fast charging technology, which allows for a quick charge of 30-60 minutes to provide several hours of use. It is important to follow the manufacturer's guidelines for charging your hearing aids to ensure they are charged properly and safely. Additionally, some hearing aids come with portable charging cases that allow for easy charging on-the-go.