Use a termination letter. This is rarely required by law, but drafting a termination letter gives managers time to carefully think through what to say and how to say it. A termination letter should explain the decision to terminate employment and a general statement of the reasons behind it.
Like many other states, Arizona is an “at-will” employment state. This generally means that employers can terminate employees at any time for any reason—or even no reason at all—without incurring legal liability. Likewise, an employee can quit at any time without providing a reason or advanced notice.
The employer may not terminate the contract before the time. The reason for this rule is that parties bind themselves in the contract for a specific time period and the commitment should be honoured. Recently in two cases, the Labour court had to determine this issue again.
While a termination letter is considered good practice, no federal or Arizona laws require it. In fact, because Arizona is an “at-will” employment state, an employer is under no obligation to provide a reason for firing an employee.
Arizona law provides that an employer may terminate an employee at any time. The term is called “at-will employment.” The legal basis for this is that the employment relationship is considered to be like a contract and at any time either party may decide to end the employment relationship. (A.R.S. § 23-1501).
Your employer can terminate you at any time for any reason, with or without notice, except for discrimination. They're not required to give you a write up. Just the same way you can quit your job at any time for any reason or no reason at all.
If you've been in your job for less than a month, you don't have to give notice unless the contract or terms and conditions require you to. If you've been in your job for more than 1 month, you must give at least 1 week's notice. It's best to resign in writing, so there's no argument about when you did it.
Regardless of what your grounds are, notice is required to terminate any contract. Typically, this notice will come in the form of a written document that clearly explains your decision to terminate the contract, why you wish to do so, and on what grounds.
(A.R.S. § 23-1501). So, generally, an employer can terminate the employee for any reason and at any time without any notice.