That's one of the great benefits of self employment. You can raise your rates anytime you want, even a dozen times a month. If you're an employee, you're lucky if you get one raise a year. However, if you're self employed and have just one client, you're in a situation more like that of an employee. However, while you'll likely only get your client to swallow one increase a year (assuming you don't sell more valuable services), you can decide how much to raise your rates, whereas am employee will only get the raise his or her employer is willing to give.