We started potty training at just over two years old and DS got the basic hang of it fairly quickly. He is now 2.5 and is reliably pooing on the toilet and does lots of wees on the potty or toilet. He understands that he should wee and poo on the potty, he can tell us when he needs to go and when he doesn't and he seems to have no fear of using the potty or adverse reaction to it.
However... Three months in he is still having frequent wee accidents, both at nursery and at home or out and about. It's particularly bad at nursery where he'll have three or four a day, but there's no rhyme or reason as to when he'll have bad days at home. He will be adamant that he doesn't need to go, then five minutes later will do a full wee in his clothes. If we use a timer and take him frequently he will either refuse to go if he doesn't want to, or do a tiny wee to appease us and then wet himself shortly after. He doesn't seem bothered or embarrassed by it though when asked he understands that he should have gone in the potty - his understanding and his speech are good for his age and he can tell us what he should have done.
We've tried a sticker chart, which didn't work, and we've tried other rewards every time he wees on the potty - he likes the reward but isn't bothered enough by it to stop the accidents, though he understands and can explain that he will get a reward if he uses the potty. He seems to know when he needs to go, and will tell us the rest of the time, so it seems to be a choice to not go to the potty, though there have been times where he has had three full accidents (soaking his pants and trousers) in a really short time period, which makes me think that there could be something else going on beyond it just being behavioural.
Has anyone been through similar and can give any tips? We really don't want to go back to nappies as he is so good with poos and totally understands what he should be doing with wees.