Simply state the facts. Probationary Period: The offer letter should indicate any probationary period and the terms of the probationary period.It's up to the employer - you should ask them. Be aware that they may be unwilling to do this until you pass the background check. The first 90 days of your employment will be under a probationary period. Most employment verification letters usually just state that the party is employed, when employment started, type of position and possibly salary. The probation period set out in the job offer letter is not proportional to the employment term. Sample Condition Language. Found 2 result(s) for your search. I need to create an employment verification letter for my new employee's probation officer.