In the morning, every 1.5-2 hours. In the afternoon every 2-3 hours. But if I am at home and notice she's wet, I change her pretty much straight away. Probably DD doesn't mind being wet, it just looks uncomfortable to me! I just ordered some nappies in the next size up, I hope we can make it 3 hours now when out, without worrying about leaking. Lately I have been checking every hour when at home, and if dry sitting her on the potty.