Maybe you heard that your employer plans to outsource your job, or you were looking for a better paying position, and your employer found out. There are several ways an employer can learn that you are looking for another job, such as receiving a fax for a reference request or a co-worker overhearing a phone conversation and reporting it.
Using Company Resources
If you use company property, such as faxing your resume or using its phones to look for another job, then your employer can fire you. You have misused company resources in an unacceptable manner. Office supply stores, such as Office Depot and Staples, will fax your resume for a minimal charge. Only give your home and cell phone numbers to a potential employer, and return phone calls on your own phone while at lunch or on your break.
On Company Time
During working hours, you should only be performing work that pertains to your job. The company can fire you if you look for another job while on the clock. The company is paying you to do your assigned tasks, and misuse of company time is a reason for immediate dismissal. Always use your personal time to look for another job.
On Personal Time
Even if you have been looking for a new job on your personal time and using your own resources, your boss can still fire you. Most state laws allow "at will" employment. This means that either you or the company can terminate the job without notice. Your boss does not need to provide a reason for dismissal if you work in an "at will" state. He can fire you at any time for any reason. It may be best to not tell anyone at work that you are looking for another job.
On Paid Leave
If your boss finds out that you are looking for another job while on paid maternity or sick leave, you can be fired without notice if your job is in an "at will" employment state. Montana is the only state that is not an "at will" work state. You are still on the company payroll, and therefore loyalty is expected.
Your employer can fire you immediately when you give a notice of resignation. Some companies consider a departing employee as unreliable or detrimental to morale. Additionally, the employer may not want other workers to know that the competition is hiring.