Ottoman's Life Hotel Deluxe
If you're staying in the Old City and want a hammam without crossing town, Ottoman's Life Hotel Deluxe is one option in Fatih, on Molla Gürani Street. It's a hotel whose health club and spa has an indoor pool, a hammam, massage and a fitness area. According to the hotel's website, women and men have separate sections. Google shows it with 4.5 from 2,531 reviews and listed as open 24 hours, but that refers to the hotel itself; spa hours are not published. Prices, treatment lengths and whether non-guests can book are not stated, so ask before you plan around it.