A Probation Period Is a Deadline for the Manager, Not a Legal Shield

Is a probation period worth having?

The date is worth having and the label usually is not. The period forces a decision onto a calendar, which matters because the alternative is a manager who defers indefinitely and a hire who finds out in month nine. It does nothing to who can be let go, or when, or on what evidence, and a handbook that implies otherwise is describing a protection nobody has.

Separate the three things the word is doing. There is a review date, which is an operational instrument with no legal effect. There is a benefits waiting period, which has rules of its own, and for health coverage those rules are federal. And there is a claimed employment status, which is where the trouble is, because it invites the reading that the standard for ending the relationship changed on day 91.

The first two survive on their own. Book the review, set the coverage date correctly, and you keep everything a probationary period was doing for you without the third thing. That is the whole recommendation, and the rest of this page is why each half of it is true.

One caveat before any of it. This page is US law as of August 2026, where employment terms are largely state law and the answer differs by jurisdiction and by whether a contract or a collective agreement is in play. Where probation is instead a contractual term carrying its own notice period, the questions are different ones and this page does not answer them. Everything below is public legal fact with its source attached. None of it is advice, and the handbook language belongs in front of counsel licensed where the employee actually works.

What does a probationary period change in US law?

Almost nothing at the federal level, and almost everything in Montana. Federal anti-discrimination law attaches to the act itself: Title VII makes it unlawful for an employer to fail or refuse to hire, or to discharge, any individual because of race, color, religion, sex or national origin ⁴. A first-week discharge sits inside that sentence exactly as a tenth-year discharge does.

The federal 90-day clock a handbook is most likely to collide with is about health coverage, and it runs against the employer. A group health plan may not apply a waiting period exceeding 90 days; eligibility conditions based solely on the lapse of time are permissible for no more than 90 days; and a bona fide employment-based orientation period is permitted only if it does not exceed one month, after which the 90-day cap starts running ³. A handbook promising health coverage after a six-month probationary period is describing a compliance problem, and that arithmetic is worth checking today. Retirement and other benefits run on their own eligibility rules and need checking separately.

One federal rule does run the employer's way, and it is narrow. Under the Fair Labor Standards Act an employer may pay an employee under 20 a wage of not less than $4.25 an hour during the first 90 consecutive calendar days after that employee is initially employed, and no employer may displace existing employees in order to use it ⁶. Nothing in it touches discharge.

Montana is the exception that proves how much the word can carry when a legislature gives it teeth. Under the Wrongful Discharge From Employment Act, a discharge is wrongful if it was not for good cause and the employee had completed the employer's probationary period, and during the probationary period employment may be terminated at the will of either party, on notice, for any reason or for no reason ¹. The companion section sets the default: if an employer does not establish a specific probationary period or state that there is none before the employee begins work, a 12-month probationary period applies, and the original period plus any extensions may not exceed 18 months ².

Read those two together and the Montana picture inverts the usual advice. The probationary period is the single most consequential date in the relationship, the default runs a full year, and an employer that says nothing has chosen that default by silence. Even there the Act is no general shield. It does not apply to a discharge that is subject to another state or federal statute providing a procedure or remedy for contesting the dispute, and the section names unlawful discrimination among them ⁷. Montana Code Annotated, 2025 edition, and this is the sort of provision that gets amended, so check the current text.

Keep the date and put a named owner on it

Book the review onto the calendar the week the offer is signed, put one person's name against it, and write down in advance what the meeting has to produce. A date with no owner is a date that moves. A date with an owner and no required output is a meeting where somebody says it feels fine, which is exactly the outcome the period existed to prevent.

Three outcomes, and the meeting has to land on one of them in writing:

• Continue. The open questions from hiring are answered. Say which evidence answered them.
• Continue with a named gap and a date. The specific thing that is missing, what closing it looks like, who is teaching it, and when it gets checked again.
• End it. With the dated observations behind it, and with the person having already heard every one of them.

The third outcome is the reason the second has to be in writing. A review that produces a decision from an impression is doing holistic combination, and that is the weaker method: in a meta-analysis of selection and admissions studies, the average correlation with job performance was .44 when applicant data were combined mechanically by a formula against .28 when the same kinds of data were combined holistically by expert judgment, across 9 studies for that criterion ⁵. The study is about hiring decisions rather than about probationary reviews, and mechanical there can mean something as plain as a written checklist with equal weights. The transferable part is that a rule applied the same way each time beats an impression formed at the end.

If your company is small enough that the manager, the reviewer and the founder are one person, the discipline matters more, and the minimum version is short: the smallest hiring process a two-person company can defend sets the same bar on the other side of the start date.

Why do so many 90-day reviews produce nothing?

Because nothing was written down between day one and day 88, so the review has to run on memory. A manager asked at the end of a quarter to characterise somebody's judgment will produce an impression, and an impression is a poor input to a decision this consequential and a worse one to explain later. The fix is a fifteen-minute weekly note, not a longer meeting.

The note is four lines and it is written the day something happens: what was handed over, what came back, what you checked, and what you found. Dated. Twelve of those is a review that writes itself, and it also gives the hire something to argue with, which is the test of whether the record is fair. A person who has read every observation before the meeting cannot be ambushed at it.

Check this against your own last four hires. Did each one have a review at the end of the period, and did that review produce a written decision? If the answer is no, the period in your handbook is decoration, and it is decoration with a legal cost in at least one state and a compliance cost in the health-coverage column. Deleting the status and keeping the date costs an afternoon.

One caution about what the period is not. It is not a licence to skip feedback, and it is not a reason to withhold the first honest conversation until day 85, which is the most common way a period designed to protect the employer produces the least defensible file. The question of how long to wait before deciding has its own answer, and the deadline depends on which failure you are actually looking at: three failures with three different deadlines. What the review consumes is the plan you wrote before the start date, which is what actually goes in a 30-60-90 day plan.

Read the evidence >