What Is a Probationary Period?
A probationary period — also called an introductory period, trial period, or orientation period — is a defined timeframe at the beginning of employment during which the employer evaluates the new hire's performance, skills, and cultural fit. Common durations are 30, 60, or 90 days.
During this period, the employer typically conducts more frequent check-ins, sets initial performance goals, and may have different procedures for termination compared to tenured employees.
While probationary periods are a common and useful management practice, the way they are described in offer letters requires careful drafting to avoid unintentionally undermining at-will employment protections.
The At-Will Problem with Probationary Periods
Here is the core issue: if an offer letter states that the employee will be on "probation" for 90 days, an employee who is terminated after the probationary period may argue that completing probation created an implied promise of continued employment.
Courts in several states have found that probationary period language can create an implied contract. The reasoning goes: if the employee successfully passed the employer's evaluation period, there is an implied expectation that they will not be terminated without cause going forward.
This interpretation directly conflicts with at-will employment, where either party can end the relationship at any time for any lawful reason.
The term "probation" carries connotations of a trial that, once passed, leads to a more secure status. This is why many employment lawyers recommend using "introductory period" or "orientation period" instead — these terms are less likely to be interpreted as creating post-probation job security.
How to Draft Probationary Period Language Safely
Use Neutral Terminology
Replace "probationary period" with one of the following:
- Introductory period
- Orientation period
- Initial evaluation period
- Onboarding period
These terms describe the same concept without the legal baggage associated with "probation."
Explicitly Preserve At-Will Status
The most important safeguard is to clearly state that the introductory period does not change the at-will nature of the employment relationship. Here is example language:
"Your first 90 days of employment will be considered an introductory period during which your performance and fit will be evaluated. Completion of the introductory period does not change the at-will nature of your employment. Either you or the company may terminate the employment relationship at any time, with or without cause, both during and after the introductory period."
Avoid Language That Implies Post-Probation Security
Steer clear of phrases that suggest completing the probationary period grants special status:
Avoid:
- "Upon successful completion of probation, you will become a regular employee"
- "Passing the probationary period confirms your permanent employment"
- "After probation, termination will require cause"
Better:
- "Upon completion of the introductory period, you will transition to regular employee status for benefits purposes"
- "The introductory period is a focused evaluation period, but at-will employment continues throughout your tenure"
Separate Probation from Benefits Eligibility
If certain benefits kick in after the introductory period, frame it as a benefits eligibility timeline rather than an employment status change:
"Health insurance, 401(k), and other benefits become effective upon completion of the 90-day introductory period. This timeline applies to benefits eligibility only and does not affect the at-will nature of your employment."
Keep the purpose of the introductory period focused on practical matters — benefits eligibility, structured onboarding, regular check-ins — rather than framing it as a "test" that the employee must pass to secure their position.
What to Include in the Probationary Period Section
Duration
Specify the length of the introductory period:
"The introductory period will be 90 calendar days from your start date."
Expectations
Outline what the employee can expect during this period:
- More frequent one-on-one meetings with their manager
- Initial performance goals or milestones
- Training and onboarding activities
- Any formal review at the end of the period
Extension Provisions
Sometimes 90 days is not enough to evaluate a new hire, especially in complex roles. Include the option to extend:
"The company reserves the right to extend the introductory period for an additional 30 days if additional time is needed to complete the evaluation."
Benefits Eligibility Timeline
If benefits eligibility is tied to completing the introductory period, state this clearly:
"You will become eligible for the company's health insurance, dental, and vision plans on the first day of the month following completion of your introductory period."
Termination During the Introductory Period
Reinforce that termination during the introductory period follows the same at-will principles as any other time:
"During the introductory period, either you or the company may terminate the employment relationship at any time, with or without cause, with or without notice."
Probationary Periods vs. Contract-to-Hire
It is important to distinguish between a probationary period and a contract-to-hire arrangement:
Probationary period — The employee is a regular employee from day one but undergoes an initial evaluation period. At-will employment applies throughout.
Contract-to-hire — The employee starts as a temporary or contract worker and may be converted to permanent status after a defined period. The conversion is a separate decision.
These are fundamentally different arrangements that require different offer letter language.
State-Specific Considerations
Montana
As noted earlier, Montana is the only state that does not follow at-will employment. Under Montana law, employees who have completed a probationary period can only be terminated for good cause. If your company operates in Montana, the probationary period has significant legal implications that must be carefully addressed.
States with Strong Implied Contract Doctrines
States like Michigan, California, and others have strong implied contract doctrines where courts have found that probationary period language created implied employment guarantees. In these states, extra care is needed to avoid language that could be interpreted as creating post-probation job security.
Probationary Period Best Practices
Document Performance
Use the introductory period to document the employee's performance through regular check-ins, written feedback, and milestone reviews. This documentation is valuable regardless of whether you keep or terminate the employee.
Set Clear Expectations
Provide the employee with clear, measurable goals for the introductory period. Written goals give the employee a fair chance to succeed and give you objective criteria for evaluation.
Conduct a Formal Review
At the end of the introductory period, conduct a formal review meeting. Document the outcome and any decisions about benefits eligibility, role adjustments, or continued employment.
Apply Consistently
Use the same introductory period terms and processes for all employees at the same level. Inconsistent application can create discrimination claims.
Align All Documents
Make sure the offer letter, employee handbook, and onboarding materials all use the same language regarding the introductory period. Contradictions between documents create legal vulnerability.
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