Thanks to the fact that it's a household name and has been around since 1850, many investors think American Express (AXP 2.56%) has no room for future growth. But recent remarks from one of its executives show it is just scratching the surface of what it could be.

The important question
At the recent Sanford C. Bernstein conference, the first question asked to Ed Gilligan, the president of American Express, surrounded the possible opportunities for growth, which were ahead for his company.

With all of the rumored speculation about what the future of payments may be, it was a great place to start. Much has been made about the possible expansion of technology firms into the payments industry.

After all, it was Gilligan's boss, Ken Chenault, American Express' CEO, who himself admitted Apple (AAPL 0.64%), Google (GOOG 1.25%) (GOOGL 1.27%), and others could change everything about the payments landscape as it shifts to be more oriented around mobile commerce.

Gilligan himself agreed, saying there has clearly been change in the industry, and much is up in the air as it relates to the evolution of the payments landscape. He himself noted, "those things will get ironed out in the next few years, whether it's Google or Apple or whoever is going to come into the space."

But it turns out, that pales in comparison to two areas where American Express is just "scratching the surface," of the opportunities to come.

The surprising answer
What are they?

While they may not grab headlines -- and are often a common refrain of many businesses -- Gilligan believes small business and international expansion are massive areas of untapped potential for American Express. And while the possible international growth was fascinating, the small business opportunity stood out to me.

Source: Flickr / Images of Money.

The massive opportunity
Gilligan began by noting American Express is "the largest player for charge and credit cards to small businesses by a wide margin, yet there's huge opportunity to do even more."

Gilligan highlighted upwards of $4 trillion is spent by small businesses in America each year. But surprisingly, less than 10% is on cards. With that in mind, American Express is doing everything it can to expand that number.

Through its OPEN business unit, it is providing solutions for small businesses to help them manage expenses, earn rewards, and simply "run their company." He notes the rewards earned by using an American Express card can in turn be reinvested back into the business, or used to pay bills.

American Express also partnered with Intuit to provide small business owners the ability to seamlessly and easily sync up their actual spending with software that tracks it. It's also ensuring its client managers are speaking with owners of these small businesses to ensure they're aware of the benefits its products provide. And it's meeting with more merchants to allow small businesses to use their cards at more places.

Gilligan concluded his remarks on small business by saying:

It's not an overnight success story. We've been doing this since the 1980s, but lately we've really perfected the business model and I think we're making real progress. When I look at where growth is going to come in the next 5 or 10 years, small businesses loom large for American Express.

The key investor takeaway
While the data to determine just how well it is executing on these iniatives is difficult to find, we have seen the growth in spending on small business cards has recently outpaced all other growth in the U.S.:


Source: Company Investor Relations.

While more clarity would be preferred, charts like the one above reveal actions by American Express to expand its small business efforts don't just sound good, the company is executing on them as well.

At times, we can think established companies like American Express have exhausted all of the possibilities for growth. But in reality, 90% of a $4 trillion world remains unclaimed in the U.S., which proves just how massive the opportunities awaiting it are.