Even before starting a family, Brittney Castro worried that someday she might feel forced to choose between her career and her children, a dilemma to which many working parents can relate. So in late 2012, she left her job as a financial planner at an advisory firm and launched her own practice.
"I wanted the flexibility to have a family and not worry about losing momentum in my career or balancing a strict 9-to-5 job" and a family, said Castro, a certified financial planner and founder of Financially Wise Women.
Castro has a lot in common with many other female entrepreneurs. Women are starting businesses at a rapid rate these days, and many, like Castro, are partly motivated by a desire for greater control and flexibility in their work lives.
Of course, owning your own business can be a more sure path to greater wealth than working for someone else, and in many sectors women are still struggling to break the proverbial glass ceiling and achieve pay equality.
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According to a study commissioned by American Express, women launched an estimated 1,300 new businesses per day last year, double the daily start-up rate for women-owned businesses in 2011. There are now more than 9 million women-owned businesses in the U.S., and they generate more than $1.4 trillion in yearly revenues, according to Amex.
While that sounds impressive, the sad reality is that most women-owned businesses are still small enterprises. Although women start businesses at twice the rate of men, only 2 percent of female-owned businesses break the $1 million threshold in terms of revenues, according to Ernst & Young, which holds a yearly competition and leadership program to help promising female entrepreneurs scale up their businesses.
The National Women's Business Council reports that only about 12 percent of women-owned businesses have paid employees.
So what's keeping many female-owned businesses from reaching their full potential? Some experts say it boils down to a few factors: a lack of capital and poor access to global markets and the need for more guidance and mentoring of female entrepreneurs. The good news is that there is a plethora of help available for women entrepreneurs, and a lot of it can be had for free or at little cost.
The U.S. Small Business Administration, for instance, oversees a national network of more than 100 Women's Business Centers that offer free training and technical help and access to loan programs.
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SCORE , an SBA partner, is another resource. SCORE is a nonprofit association that offers free, confidential counseling for entrepreneurs. It has more than 320 chapters across the country, and about 11,000 business experts serve as volunteer mentors for the program.
The SBA also operates a network of U.S. Export Assistance Centers, which are staffed by professionals from that agency, the U.S. Department of Commerce, the Export-Import Bank and other organizations. The centers are focused on helping small businesses compete in the global marketplace.
"The resources need to be there to empower women-owned businesses to grow, and that is what we have focused on at the U.S. Small Business Administration," said Erin Andrew, the SBA's assistant administrator for the Office of Women's Business Ownership.
Female entrepreneurs, said Andrew, tend to rely heavily on personal savings to fund their ventures, which can hamper their ability to hire employees and invest in critical assets. Men, she added, are much more inclined to use bank loans and unconventional capital sources, such as loans from family and friends.
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The capital gender gap is partly due to the fact that many women-owned businesses are relatively new and small, and bankers aren't always eager to lend to such companies, regardless of whether the firms are owned by men or women, according to an SBA report. In addition, female entrepreneurs rarely network with executives from venture capital firms, which tend to be male-dominated, and are underrepresented in fast-growth and high-tech sectors.
For its part, the SBA is striving to put more capital in the hands of women business owners. Earlier this year, the agency launched an online tool, called LINC, which connects entrepreneurs with SBA lenders around the country.
Users fill out a simple online form, and any interested lenders contact them within 48 hours. Applicants also receive information about local SBA partners that offer free business consulting and low-cost training programs.
"Getting more women into the pipeline to take on debt is important," Andrew said. "Part of that entails making sure they have relationships with banks." She added that her agency has waived fees on SBA-guaranteed loans under $150,000 to make lower-dollar loans more affordable.
The SBA's LINC tool is just one way that the Internet is helping to break down barriers when it comes to access to capital, markets and low-cost services, such as legal help.
Sites like Etsy, the online marketplace focused on crafts and vintage items, have become an important platform for many entrepreneurs. Crowdfunding sites, including female-focused Plum Alley, are also changing the status quo.
Some large corporations are courting women-owned businesses through supplier diversity programs. Kari Warberg Block, founder and CEO of Earth-Kind, took advantage of such programs when she launched her line of natural pest-control products in 2007.
Block said she landed meetings with buyers for Target, Lowe's and Wal-Mart thanks to such programs. Today, Earth-Kind's products are sold in 55,000 stores. The company generated more than $4 million in revenue last year.
"Supplier diversify programs get you to the table and put you on a fair playing field," said Block, adding that women-owned businesses have had a harder time breaking into certain industries, and pest control is among them. "In the end, though, you have to be better, faster and cheaper in some way," said Block, a self-described former "farm wife" from North Dakota turned entrepreneur. She is a new member of the National Women's Business Council, a nonpartisan federal advisory council.
While it is never easy to launch and grow a business, there has perhaps never been a better time to be a female entrepreneur, said Jaime Nack, founder and president of Three Squares, a sustainability-consulting firm.
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After working in local government and for a private-sector environmental consulting firm, Nack launched Three Squares in 2008 and in 2013 rolled out its sister company, One Drop Interactive. Unlike women of previous generations, today's female entrepreneurs, she said, don't need to go it alone, and they shouldn't. Nack is a former member of the National Women's Business Council.
Being involved with an organization that is focused on supporting women-owned businesses "pushes you to scale your business even further, especially when you get involved with one that commissions research and you are reading all the studies," Nack said. "It makes you feel compelled not to be a statistic."
—By Anna Robaton, special to CNBC.com