We started giving Claire water when she was about 6 - 7 months. Around the same time that she started to have solids. The watrer wasnt to replace breastmilk, it was just something extra for her. We did start off with giving her cooled boiled water. The nurse recommended we do this until she is 12 months. I dont bother boiling water any more. I just give it to her straight from the tap.