PwC is one of a handful of companies offering to pay part of their employees' student debts, an increasingly popular perk.

Following PwC's announcement over the summer, Natixis, an asset management firm, will announce its own student loan repayment program today, Tuesday, Dec. 8.

The company will contribute up to $10,000 toward student loans and is making the perk available to any of the company's 525 U.S.-based employees that have been with the company for at least five years.

Nataxis will pay the benefit in lump sums: $5,000 after five years of working at the firm, followed by annual $1,000 payments over the succeeding five years.

Student loan payment programs are still a relatively uncommon perk.

Only 3 percent of more than 450 surveyed companies offer student loan repayments programs as a part of their benefit plans, according to the Society for Human Resource Management's 2015 Employee Benefit Survey.

Some predict that companies will soon catch on in a big way. "Those numbers are understated because there is a lot of pent-up demand for this stuff," said Bruce Elliott, SHRM’s manager of compensation and benefits. This was also the first year SHRM included the benefit on its survey. "I do think it’s the beginning of a trend."

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So far, companies that hire swaths of college grads—a group that tends to have a lot of debt—are at the forefront of the trend. PwC, for example, plans to hire more than 11,000 through campus recruiting this year.

Most employers tend to put from $100 to $250 a month toward an employees's debts while capping the amount they'll contribute, said Tim DeMello, founder and chief executive of Gradifi, a platform that helps employers such as PwC contribute to employee student loan payments.

An employer's contribution probably won't cover its workers' entire debt load, but it can make a meaningful dent. Some companies offer loan refinancing reductions, a slightly different, related benefit.

"We're seeing that it always comes down to meaningful contribution," said DeMello. Gradifi has signed up nearly 100 employers, including PwC and some other "high profile" clients, DeMello said. The company will start rolling out payments at the beginning of next year.

"Anything helps when it comes to paying off a loan," said Gutierrez, 23. She is currently saving money to move out of her parents' home in Northern Virginia. "One hundred dollars a month is a great help to me."

As with many benefits, employers hope student loan assistance will help attract and retain the best workers.

"We're a very innovative company; we rely on innovation to move us forward," said Ed Farrington, executive vice president of business development and retirement at Natixis. "In order to continue that edge, we have to attract the best and brightest."

As the economy has improved, employee retention and turnover is one of the biggest issues facing employers. Employers have offered an array of strategic perks, including generous paternity leave, to battle attrition, and Natixis hopes being at the forefront of the benefits trend will give its organization an edge.

There's another advantage to piling on benefits as a recruitment tool. If the economy sours, it's much easier to cut a benefit than a salary; employees don't feel the sting as much. "They are flexible," said SHRM's Elliot. (Some surveys indicate that employees value benefits more than pay raises.)

Still, not all perks are created equal. Health care was the top-rated benefit for employees in terms of importance, probably because it's a high and rising cost.

"Employers aren't doing this to be nice," said Elliot. "They're doing this as an investment—and to differentiate themselves so they can continue to pull from the top of the talent pool."

Although few companies offer student debt assistance, it ranks high among coveted perks, especially for millennials, who make up one in three American workers—a share that's expected to grow to almost half by 2020.

A recent survey by Iontuition, a student loan management platform, found that 80 percent of the 1,000 people surveyed wanted to work for a company that offers student loan repayment assistance.

Paying off debt has more immediate benefits than, say, taking advantage of a company's 401k plan. "Employees love this benefit," said Brendon McQueen, the founder and chief executive of Tuition.io, a payment platform that works with employers. "They already understand the pain of student loans. You don't have to educate them on what a 529 is. People already get it. They're like, 'Where do I sign up?'"

Gutierrez hasn't tapped into PwC's retirement benefits yet.

She's more concerned with paying off her loans. "I'm also paying off a car payment, and I wanted to make sure I could save up as much as possible right now to be comfortable when my loan payment began," she said.

Despite enthusiasm from workers, adoption and implementation has so far been slow. PwC announced its program earlier this fall, but it doesn't plan to funnel money into employees's accounts until July.

"It's pretty complex," said Tuition.Io's McQueen. "[For] employers who don't have this ... it's super-hard to build products that are outside of their core business." Some companies are also waiting to see if the benefit works before they promise it to employees.

Like many trendy benefits, this perk will help only a small, elite portion of the workforce.

Over the next three years, however, Elliot predicts that debt repayment, on some level, will become as common as health benefits.

"It's a big-ass problem: $1.3 trillion is a big number." said Gradifi's DeMello, referring to the national student debt balance. "These types of initiatives are going to really help."

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