As a jobseeker, it's easy to feel like any job opportunity is a good one. You want to advance your career. You want to grow your skills and be part of a team. You need a paycheck, of course.

Still, you don't always need to say yes. "Getting to a job offer is a great thing," says Amanda Augustine, career expert at TopResume. "But that doesn't mean that you should accept it just because you got the offer." Some places are not a good fit for various reasons, and you'll want to suss that out before you agree to anything.

Here's how to tell if a job opportunity is right for you, and how to walk away if it's not.

'Listen to your gut'

There are multiple reasons a role might not be the right one for you. The first is simply that the job currently does not fill your needs.

Before you go into any interview process, you "have to have your own personal list of your must-haves," says Stacie Haller, chief career advisor at Resume Builder, "and then the things you're willing to maybe do without."

DON'T MISS: The ultimate guide to negotiating a higher salary

Your must-haves could be things like a salary range or a certain level of flexibility. Lower priorities might be a specific amount of vacation or sick time. If the offer they give you can't match your must-haves — even after you've tried negotiating — it might be time to walk away.

The second reason a job might not be the right opportunity is that you detect it has a certain environment that wouldn't be best for you. When you go into the office for the interview, pay attention to what you're seeing. "Does there seem to be a happy banter going around?" says Augustine. "Or do people look miserable and stressed?"

Pay attention to how they treat you in the process as well. "If there's something that is bothering you about the offer or the process," says Haller, "it's an indication of what it's going to be like when you work there."

"Listen to your gut," says Haller, adding, "a red flag is there for a reason."

'Be honest but diplomatic'

Whether you realize the place is not right for you during the interview process or once they've extended an offer, politely let them know you're not ultimately interested.

Say something like, "thank you so much for taking the time to speak with me," says Augustine. "It was great learning more about this. However, as [I've] learned more, I just don't think it's a right fit for me."

You can be more specific and let them know it doesn't offer the kind of growth you're looking for or the salary doesn't match your needs.

The point is to "be honest but diplomatic," says Augustine. That's both out of respect and to ensure you don't close any doors for yourself in the future.

"Leave on a good note no matter what," says Haller, "because you never know when those people are going to cross your paths again."

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