It’s the last stop during your in-house interview, and you’re knackered. As you wait for human resources to arrive, you’re adding up the things you should have done differently that day. As the HR rep enters the room and sits down, you still have time to make one more mistake, and it could be the biggest of the day. She starts naming the perks awarded to everyone from janitor to CEO, such as paid holidays, sick leave and a bathroom with free toilet paper. Then, she throws out the number you’ve been waiting for: a starting salary. Do you accept the offer or start negotiations?

The answer, research suggests, depends on your gender.

If you’re a man, you’ll likely shoot back a counteroffer and justifications for your worth. If you’re a woman, you’ll likely forgo negotiations and either ask where your new desk is or reject the offer and walk away completely. But take heed. When a woman makes the mistake of not negotiating her starting salary, she stands to lose a minimum of $500,000 by the time she reaches age 60, according to the authors of “Women Don’t Ask: The High Cost of Avoiding Negotiation — and Positive Strategies for Change.”

For years, numbers have trickled out of government agencies and nonprofit think tanks about the gender wage gap. Recently, research has shifted to examine why the gap exists at virtually every level in an organization. Much of it has to do with negotiating and the fact that women simply don’t ask.

Females’ salaries average 82 percent of their male counterparts’ just one year out of college, according to a 2012 report by the American Association of University Women. The wage discrepancy is also evident in management positions.

Economists refer to these lost wages over time as the “accumulation of disadvantage,” and there are a number of reasons for it. Women don’t know when it’s OK to negotiate. When they do, they talk themselves into asking for less, or worse, a woman can be perceived as the office harlot if she asks the wrong way.

Recent findings by the National Bureau of Economic Research show that women are more likely to negotiate if the job ad mentions a wage range. Conversely, men prefer jobs where “rules of wage determination” aren’t clearly defined. This is because women like to know what the rules are and play by them, says Lee Miller, a career coach and co-author of “A Woman’s Guide to Successful Negotiating.”

“It’s one of the mistakes women make,” he says. “If they don’t know that the rules allow you to negotiate — or they think that they don’t — then they just don’t negotiate. As soon as you tell them they are expected to, then boom, they’re very happy to and many times can do a better job than a man. Men aren’t so bound. They are constantly breaking the rules, so to speak, and they just instinctively start.”

Almost all men try to negotiate some aspect of their compensation, even if it’s not salary, Miller says. This could be paid time off, working from home or a cell phone stipend. Men view the world as full of opportunity and choices, while women have low opportunity-recognition for negotiation, says Sara Laschever, co-author of “Women Don’t Ask.”

“Women think if there was more available, then they would have been offered more,” she says. “If negotiation was possible, then someone would have said that. Women are more likely to think, ‘You just need to make the best of whatever situation you’re in.’ A man will look at multiple opportunities and seek out the best one.”

Throughout their careers, women tend to assume their employer will offer a raise if the boss thinks she’s worthy. They are unlikely to ask based on their own self-worth, whereas men will commonly ask to be rewarded. If he isn’t rewarded, he’s more likely to look elsewhere.

“Women tend to be more loyal to their organizations or less mobile,” Miller says. “They are less likely to leave, and that hurts them in negotiating. If your employer knows you aren’t going anywhere and knows you aren’t at risk to leave, they are less likely to give you money or give you as much money as if they thought you might leave.”

Another reason women won’t ask for raises as often as men is what psychologists call “locus of control.” It’s used in studies and quizzes about careers to examine if people believe the events that affect them are internal or external. Men exhibit internal tendencies and are inclined to believe they control their own destiny.

“Women, on the other hand, think the locus of control is external and that other people decide their worth,” Laschever says. “If you think someone else has that power and that authority, then you are less likely to challenge them.”

Women typically don’t like that challenge and view negotiations as conflict. Unfortunately, people in her office might agree. Some research suggests that female workers who ask for more money are perceived as unpleasant by their co-workers. It’s another reason why women wait for the green light to negotiate, says Yasmin Davidds, founder and CEO of the Women’s Institute of Negotiation.

“Research clearly shows there is a high social price women pay when they do negotiate,” she says. “They are labeled as ‘more difficult to deal with’ and less ‘likeable.’ When a job ad mentions a salary is open for negotiation, it’s giving women permission. It’s telling women that they will not be punished if they negotiate. Therefore, women feel confident they will not experience backlash.”

Miller disagrees with this research emphatically, instead arguing that women are often set back not by unwillingness to negotiate but by the way they approach the conversation. A woman shouldn’t ask the same way a man should. And a male Lilliputian shouldn’t ask the same way as a male who’s 6’4”. It boils down to psychology.

“Different people bring different things to the table,” he says. “Women bring certain advantages. Why would you try to negotiate like someone else? Men who are tall have a certain amount of intimidation they can use. If you’re 5’7”, you can’t do that.”

One advantage for females is they are perceived as more trusting during negotiations.

“So when a woman says something — in the right way, with quiet, firm confidence — it is much more likely to be believed,” Miller says. “We assume that men are playing games when they negotiate, so women can use this to their advantage if they do it right.”

When women are negotiating, their style, manner and behavior is much more critical than it is for men. A man is more likely forgiven for aggressive negotiations, even seen as a shrewd and cunning businessman. A woman using the same tactics can be seen as a shrew. 

“If people perceive women as behaving in an overly aggressive way, they often feel that they are threatening,” Laschever says. “We react negatively. And it’s both men and women who don’t like women who they perceive as too aggressive. Negotiation is often seen as a fairly aggressive action, so for a woman to be effective, she must be likable. It’s not enough for her to have a good argument.”

Laschever suggests that women practice role-playing beforehand. Get someone to play the interviewer and give honest feedback. They can say things like, “You should really smile when you say that because it softens the message.” Or, “I don’t think you realize that when you’re listening to me, you are kind of frowning and looking off into space.” Or, “You’re not likable.”

It’s helpful for both men and women to practice interviewing, but Laschever says women face more risk of losing ground if they aren’t liked. As long as men are competent, their social mannerisms aren’t as important. So if a woman isn’t likable, co-workers might view her as Cruella de Vil, but if she’s too friendly, then she’s Julia Roberts in “Pretty Woman.”

A recent study out of UC Berkeley suggests women can get ahead in negotiations if they turn up the “feminine charm.” However, Laschever warns against getting too friendly.

“Research shows that flirting can be an effective strategy in the short run, but it reduces [perceived] competence over the long term,” she says.

While negotiations play a big role in closing the wage gap, it’s just one contributing factor found in the research. Women also outnumber men in low-earning professions, and people tend to devalue women’s work without realizing it. There won’t be equality in pay until there is widespread social and cultural change in the workplace, Laschever says.

“Negotiations is the big one that women need to pay attention to because it’s something they can do something about,” she says.

Miller has worked in human resources at TV Guide Magazine, USA Networks and Barneys New York Inc. In all his years dealing with salaries and negotiations, he rarely saw a man accept the first offer.

“But I saw many women just accept what was offered,” he says. “Or — and this even worse — simply not accept the job without trying to negotiate.” 

HOW TO NEGOTIATE YOUR SALARY IN ANY ECONOMY

If someone wants to hire you, it is because you offer something they value. As a result, you are in a position to negotiate for additional money, benefits and opportunities. There are, however, right and wrong ways to go about it. Here are a few tips to help you negotiate more effectively:

Take the time to learn how to negotiate. Like good writing and math, negotiating skills have to be learned. Take a class, attend a seminar or read a book on the topic. The ability to negotiate effectively will help you throughout your working career.

Get the buy-in. Get a potential employer to fall in love with you before you talk about money. The time to be asking for things is after an employer has already decided to hire you. Focus on what is important to the employer and what you can do for them. Employers want to hire people who bring value, and they are willing to pay what is necessary to hire quality people. Once the employer has decided to make you an offer, then — and only then — should you start discussing the details of employment. If asked what you are looking for in terms of compensation earlier in the process, say something like, “I am sure that if I am the right person for the job and the job is right for me, something that is fair will be readily worked out.” Then ask some questions about the job.

Don’t act like you are negotiating. Remember, once the employer has decided to offer you a job, they are trying to recruit you. Let them. Don’t make demands. Tell them your concerns. Ask for the things you want without ever suggesting that you won’t accept the job if you don’t get them. “Would it be possible…” or, “Could you…” or, ‘Other companies I have been talking to have offered….” are non threatening ways for you to ask.

Negotiating is not only about salary. Understand how a prospective employer structures their compensation, and seek what is easiest for an employer to give. For some employers, that is salary; for others it’s bonuses or stock. Often, particularly early on in your career, the most important thing that you can negotiate is the chance to learn new skills. Among the things you can negotiate are the types of projects you will be assigned, who you will be working with and what training you will receive.

Regardless of the state of the economy, most employers are not trying to hire the person that they can get for the least amount of money. They are seeking individuals that add real value. If an employer offers you the job, you are in a good position to negotiate your compensation. Understanding these principles will allow you to effectively negotiate the best possible terms in your next job, regardless of the state of the economy.

A veteran human resources executive, Lee Miller is a career coach and the author of “Get More Money on Your Next Job… In Any Economy” and, with his daughter Jessica Miller, “A Woman’s Guide to Successful Negotiating.” Lee can be reached at Lee @employability-expert.com

LOOKING FOR MORE NEGOTIATION RESOURCES?

Sara Laschever and Linda Babcock, authors of “Women Don’t Ask: The High Cost of Avoiding Negotiation — and Positive Strategies for Change,” helped to launch the Heinz Negotiations Academy for Women at Carnegie Mellon University. The $15,000 academy in Pittsburgh, Pa., launched its first class in January and teaches women how to identify new opportunities and gain self-confidence over a 5-week course through lectures, case studies, interactive exercises and one-on-one coaching. A student of the academy should have a sponsor from her organization to help set, measure and achieve goals.

Yasmin Davidds, founder and CEO of the Women’s Institute of Negotiation, wrote a book due out this fall titled “Game Changer: How Women Can Negotiate with Power and Grace to Level the Playing Field.” It includes real-world scenarios she conducted over a 5-year period while teaching negotiation skills to professionals in 22 countries. It includes examples of negotiation successes and failures from women around the world.