You won&#x27;t get charged twice on any well-written site, but I&#x27;m still careful with the back button around any transaction.<p>It&#x27;s not really an issue at either of my banks, because a transaction is a lot more than merely submitting a form, and requires authorization with a single-use code. But webshops tend to have far more linear transactions, and I don&#x27;t always fully trust them to use the back button the way I think it should work.