Here’s what most people get backwards about probationary periods: they assume that once you pass probation, you get real protections — and during it, you have none. It’s actually more complicated than that, and in most cases, both halves of that assumption are wrong.
In most U.S. states, employment is “at-will,” which means your employer can let you go at almost any time, for almost any reason — whether you’re on probation or not. The Texas Workforce Commission puts it plainly: the idea that probation is a special unprotected zone, and that passing it locks in your job, is a common misconception. Probation usually doesn’t change your fundamental at-will status either way.
One notable exception: Montana has a law called the Wrongful Discharge from Employment Act, which means that once you complete a probationary period there (typically six months to a year), your employer generally needs “good cause” to fire you. If you live in Montana, your situation may be meaningfully different — and it’s worth looking into.
But here’s the part that actually matters everywhere: “almost any reason” is doing a lot of work in that sentence. As long as the real motive behind the firing isn’t illegal, the firing is legal — but if the real reason IS illegal, it doesn’t matter that you were still on probation. Being new to the job doesn’t erase your civil rights.
So what counts as an illegal reason? Things like firing someone because of their race, gender, religion, national origin, disability, or age. Firing someone for reporting illegal activity (that’s called retaliation). Or firing someone in violation of a specific contract or law that applies to their situation. These protections exist regardless of how long you’ve been on the job.
Even federal probationary employees — people still in their first year working for the U.S. government — have some protections. When the Trump administration tried mass-firing probationary federal workers in early 2025, a judge ruled it was illegal, partly because even those employees can’t just be dismissed without following proper procedures. They can be let go for bad performance or conduct, but the process still has to be legitimate. (Note: this applies specifically to federal government jobs, which have their own separate rules.)
Bottom line: probation means your employer has more flexibility to let you go without needing much of a reason. It doesn’t mean they can fire you for an illegal one. Employment law also varies by state, so if you think something went wrong, it’s worth getting advice that’s specific to where you live. If you think you were let go because of discrimination or retaliation — not just because you were new or struggling — that’s worth taking seriously.