"What is your current salary" is one of the most common questions you'll be asked in an interview. But you should never answer this question and be ready to accept they might not choose you anymore.
Here is what you can do to deal with this question.
The reason for this question is pretty simple. Salaries are one of the hugest cost factors for companies, and minimizing those is one of their main goals.
Why should a company pay you 200k if your previous salary was only 120k? Well, that's at least their reasoning. Especially when your previous and future tasks are comparable, why should you magically be worth so much more?
Having a number at hand makes it pretty easy for them to negotiate with you. A little more salary is okay but too much? Nah! If you give them a number, they pretty much got you. They'll be able to determine what to pay you to still be attractive for a job switch, and always have a reason for why they won't pay you more.
Never. Ever. Answer. This. Question. Period.
And never ever lie about your previous salary. As already said, if you answer this question, they got you, and if they catch you lying, you're done, as well.
Really: Politely deny answering this question.
If they still insist on getting an answer because they "can't go on with the process without an answer" or whatever they come up with, still deny the answer. Better try to circumvent an answer to this question as best as possible.
Better say something like this:
"Sorry, I can't talk about my current salary, but in my current job search, I look for jobs with a salary range of $x.y k and $z.a k, and I think that the experience and knowledge I bring with me is well worth this investment."
And if you haven't talked about a salary range already, feel free to add: "Does this position provide a salary range that is close to my expectations?".
If the company can't accept you not answering: Be ready to drop out of the process!
It's better to get paid what you deserve and could fairly negotiate for than to accept being underpaid greatly because you simply made the mistake of making your current salary transparent.
This one question is one of the most important ones in an interview, as it can have such a large impact.
In my opinion, it's a huge mistake to ever answer this question as it gives too much power to your potential future employer, and takes away a lot of your own power.
You won't be able to negotiate for what you're really worth after answering it. Circumvention of this question does, however, often work. It may sometimes not, but then ask yourself: "Is this really a company I want to work for?".
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