While jumping ship after the fact may not be a career crusher, it can have a chilling effect on your future hiring.

For job hunters interviewing for multiple positions, finally receiving that offer can be a great relief—more so once you’ve accepted and the paperwork is signed.

But what happens when more than one company wants you and suddenly you’ve accepted one only to have a second, glitzier offer arrive. Some might say you’re in an enviable position. But for many, this is a problem. Do you back out of the first agreement and take the dream job?

What’s right for you?

If an offer comes in shortly after you have accepted another one or right after you’ve started, there’s nothing wrong with taking a look at the other company, according to Fred Kiel, co-founder of Minneapolis-based leadership consultancy firm KRW International. “Changing your mind in the first few days of a new job is still okay,” he said in an email because this company has not yet spent significant time and resources in getting you in.  “Everyone can find themselves in this situation, and to resign after a few days on the job will not be considered a cardinal sin.”

Plus, it’s better for both sides that you are in the job that you feel is the right one, said Jorg Stegemann, head of Kennedy Executive Search & Outplacement, with offices in Paris, Frankfurt, Milan, Prague and soon in Amsterdam, in an email. “My experience is that unless you give 100% commitment, you will not be successful in most jobs. This means that you will not become a top performer and get a promotion after three years, the normal “lifetime” of a job. It also means that it creates frustrations: in you and in your hiring company.” 

An ethical dilemma

Be careful though. While jumping ship after the fact may not be a career crusher, it can have a chilling effect on your future hiring, especially in fields where the community is quite close-knit such as cybersecurity and fashion.

Much of the decision boils down to an ethical versus personal one, according to Adam Lloyd, president of global executive search firm Webber Kerr Associates in Tampa, Florida, in the US. “This is a career-delicate situation, often without a purely optimal outcome,” he said in an email. “Once you’ve made a commitment and signed with an organisation, it can be very damaging and irreversible to walk away. Talent pools within industries and markets are very small; this could affect future career moves and your reputation.”

While the ideal moral decision would be to fulfill the initial commitment, sometimes a new offer is simply too good to pass up. In that case, Lloyd advises that you carefully map out all of the immediate and long-term pros and cons of both positions before jumping ship. “The monetary compensation is only one factor that contributes to overall job satisfaction, so think of the culture and the people you connected with, advancement opportunities, autonomy, or whatever you value most to aid in a happy professional well-being,” he said.

If you still decide that the new offer is better, then it’s time to start the process rolling.

Say sorry

Once you are committed to rescinding the initial offer, have your terms legally reviewed and also verify that you have a tangible formal offer from the second company.

Then it’s time to apologise. “Do not let time lapse in contacting the initial company, and approach the situation as humbly and apologetic as possible,” said Lloyd, who once witnessed a candidate who went so far as to provide referrals for a replacement.  “It’s tough to recover from this scenario, but all of the little thoughtful attempts help,” he said.

If there was a hiring company involved, you need to call them up, said Stegemann. “Yes, this call hurts,” but it is the best thing you can do to turn a lose-lose situation into a potential win-win for both sides, he said. You get your dream job and the company doesn’t have to settle for an employee who would rather be someplace else.

Avoid sending an email, according to Kristen Coppins, a Boston-based director at Professional Staffing Group. "Doing so by phone and in a live conversation is the most respectful way to do it,” she said. “Keep your explanation simple and straightforward and explain that you're making a tough decision but one that is the best professional decision for you and will best advance your career."

Avoidance is best

If you can, it’s better to avoid getting in the situation in the first place, said Coppins. “It's important to do your research and understand timelines. For example, know when the offer will be coming and how long it's good for. Be clear about your own timeframe, too,” she said.

Mark Zafra, a senior director for a northern California financial services company, has been on both sides of the hiring table. “[It’s] very frustrating and unprofessional” when a candidate backs out of an offer, he said in an email. For Zafra, the best way to avoid it from happening is to time things well and to be upfront. “I have always delayed in order to have both [offers] on the table before accepting,” he said. “Also, I make sure to tell the recruiters that I am ‘anticipating an offer in the next week.’ Especially if I really want one.”

Career Coach is a twice-monthly column on BBC Capital in which we consider the career turning points and questions many professionals face. We welcome questions from readers at careercoach@bbc.com.

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