So, you need to cancel on a client, maybe because your workload’s just too heavy to handle another meeting, or because something else came up. Or maybe you’ve met with them several times before and thus your interactions have become repetitive, if not unproductive.
It’s tricky—especially because the main part of your job is to, well, deal with clients, so canceling on them doesn’t look great. The first thing you have to consider if you ever want to back out on a client is your company’s relationship to them. All clients are important, but some carry more weight than others in your priority list. So ask yourself, where do they fall in the hierarchy? Do they contribute a lot of business to your company’s bottom line? If so, there’s probably no great excuse not to meet with them (unless you’re say, horribly sick or dealing with an emergency). Also, consider your excuse—do you just hate meetings, or do you actually need to reschedule for a valid reason?

Read more at: http://www.virtuedigest.com/how-to-politely-decline-a-meeting-with-a-client/