You can be flexible too: Call during dinner time, at 11 p.m., whenever it's convenient for you. This can be especially effective when you're in different time zones.

Remember, if you don't respect regular working hours as a boundary, neither will your remote employees, and that means the company will get even more work out of them.

9. Call remote employees only when you have a specific purpose

With remote employees, call when you have something specific to say or to ask. Especially, call on thin pretexts to verify the employee isn't slacking off.

But don't call on a regular basis to have the sorts of casual conversations you conduct with on-site employees. Make it policy: Remind all employees that telephones are business tools, not to be wasted on non-business-related conversations.