You are free to cancel your service at any time on a month-to-month service. However, you might incur extra charges if you are on a contract or if you have used excess inclusions during your current billing period.
When you do cancel your service you will lose your unused monthly allowance, so if you'd like to make the most of your service, then it's better to cancel towards the end of your billing cycle.
Want to learn how to cancel your service? Click HERE to find out.