Aaron Houghton and Ryan Allis, the former UNC-Chapel Hill students who launched e-mail marketing firm iContact, are No. 4 on the list of top CEOs under 30, according to the small business website Under30CEO.

The list, which was published Thursday by Reuters news service and Under30CEO, is packed with some of the best-known young faces in high-tech today.

No. 1 is Facebook’s Mark Zuckerburg, who also was Time magazine’s Person of the Year for 2010 and whose company is the most popular global social media website.

Andrew Mason of Group is No. 2.

Matt Mullenweg of WordPress is No. 3.

Selections were based on nominations from and voting by Under30CEO readers.

“Influence was asked to be judged on how much the person’s ventures were impacting the world and the way we live everyday,” Jared O’Toole, co-founder of Under30CEO, wrote. “This entire group is tremendous and together their ventures are valued near $100billion and reach millions if not billions of people across the world.

“While most of these companies are private, we’ve done our best to find as much financial information available about their companies.”

Allis and Houghton are very active philanthropists, being especially supportive of Nourish International.

Houhgton is also founder and chief executive officer of Preation, a web marketing tools company based in Durham.

The two shared Carolinas Entrepreneur of the Year honors in 2009.

“Ryan and Aaron started iContact in 2003 to help small businesses better manage their email marketing campaigns,” Under30CEO says. “The company started by solely marketing through Google AdWords and has grown to over 63,000 customers today. In August 2010 iContact closed a new round of funding at $40 million.”

Houghton is 29, Allis 26.

 Read the full Under30CEO list here.

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