Are there any laws in the UK stipulating against disposing of mobile phone chargers in household waste?
There might be issues with disposing of the battery, otherwise it’s fine. Certain charities accept old mobile phones. They will take them and each one is recycled, and a certain amount, usually at least £1, is donated to charity. I got rid of a couple of my useless phones like this, and I also traded in my old phone, complete with charger and accessories, for money off my new phone, when I bought a new handset from the O2 Store.