Peeing on bed

[TimrousBeastie]

My 18month old dog has just started to pee on my bed (shes not neutered and not in season if it makes a difference) and advice on how to stop it? Have no idea why shes doing it as nothing has changed

Is this where she sleeps? Or do you get the impression it is done to make an impression?

Firstly check for UTI with vet, once that is all clear address the behaviour. Is it while she is asleep, before you go out, when you get back etc?

More detail required.

Assuming you don't mean she's suddenly become incontinent and is doing it involuntarily (in which case you need a vet), can't you simply shut her out of your bedroom, and only allow supervised access? If she is peeing at night while sleeping with you, make her sleep elsewhere. Has she got a bed of her own?