A college degree or professional certificate is a clear advantage for anyone hoping to make a living wage, but millions of Americans have neither, despite taking — and paying for — college courses.

An estimated 31 million adults have some college under their belts — some as much as two years’ worth — but no degree to show for it, according to a July 2014 report from the National Student Clearinghouse.

Community college students often fall into this category, notes Joe May, chancellor of the Dallas County Community College District. These students often work full or part time and take one or two courses at a time.

“As a result, they slowly accumulate the credits they need to earn a degree or a certificate, chipping away at their credentials,” he says.

Along the way they gain valuable work experience — sometimes in their chosen field — and, in some cases, a better sense of their career paths. The clearer picture can help motivate students to recommit to earning a degree, but it can also raise new questions, such as whether to complete their associate degree or transfer the credits toward a bachelor’s.

[Get advice on making the leap from community college to a four-year university.]

Time and money are two major factors to consider in this decision, experts say.

“Which option will enable the student to finish the bachelor’s degree with the lowest cost, in the quickest amount of time?” says Colleen Ganjian, a college counselor in the District of Columbia.

For Ben Nettleton, 33, the clear answer was to finish his associate degree.

Nettleton built up college credits as a high school student in Minnesota, but those courses didn’t prepare him for the reality of life at a four-year university. He lasted a few semesters in the computer science program at the University of Minnesota before dropping out.

“It was way more of a struggle than I was prepared for,” he says.

[Learn how to build a network as a community college student.]

After several years of working random jobs — tour guide, window washer and sales associate, just to name a few — Nettleton started thinking about going back to school. But he had reservations.

“The hiccup I experienced with the computer science, it really threw me for a loop. I sort of thought, maybe this level is just not in my skill set,” he says. “And, as time goes by, there’s a lot more at stake to go back to school.”

So Nettleton called an adviser at the community college he attended in high school and learned he was just a few credits shy of earning an associate degree.

“I had two semesters of easy peasy classes and I would have an AA,” he says. “It would have been foolish not to.”

The associate degree from Ridgewater College helped him get his foot in the door at his current job with a nutritional supplement company in Houston and, if he decides to get his bachelor’s down the line, he thinks his associate degree will be easier to transfer than a random assortment of college courses.

May, with the Dallas County community college system, says this is the way to go.

“We urge our students to complete what they’ve started — to finish their associate degree or professional certificate — and then transfer to a four-year institution to pursue a bachelor’s degree, if they choose to continue their academic career instead of entering the workforce directly,” he says.

[Explore four tips to help you finish community college.]

Having a college degree gives graduates an edge when applying for jobs and helps boost their earning potential, May notes.

“If they transfer before they complete that credential, their earning power is affected while they continue their studies in college,” he says. “If they don’t finish their bachelor’s degree, they have no credential whatsoever to help them qualify for a job that pays well.”

But Darrell Gurney, a California-based career coach and former recruiter, says if a bachelor’s degree is the end goal, students should transfer and go for it. Gurney’s own 20-year-old son is “dabbling at education,” he says.

“When he gets clear on the direction he is actually committed, of his own right, to pursue, then I believe transferring any credits and getting on track for that four-year degree is appropriate,” he says.

An associate degree is a sufficient credential for some career paths — nurses, for example, can get entry-level work with an associate degree in nursing — but other fields, such as teaching, require a bachelor’s degree for even entry-level positions and professional licensure. If students can only get their foot in the door with a bachelor’s, their time and money may be better spent pursuing that degree.

Commitment and motivation are key, though. Nettleton advises students to ease back into it if they only have a semester or two under their belt. Then, if they have the support and the “moxie,” commit to a major degree program.

Trying to fund your education? Get tips, news and more in the U.S. News Paying for Community College center.

More from U.S. News

Build a Network on Campus as a Community College Student

4 College Savings Tips for Community College Students

4 Types of People Who Benefit From Community College

Figure Out When to Switch Gears From an Associate to a Bachelor’s originally appeared on usnews.com