If you're like most investors, the bulk of your stock holdings are familiar names. There's nothing inherently wrong with that. We're supposed to hold names we understand and can monitor, after all, so we tend to gravitate toward companies making lead headlines. There's a lot to be said for taking the road less traveled, though. Familiar stocks are often crowded traded, pumping up the premium you pay for them. Smaller -- or at least less visible -- companies are often buried treasure nobody's even trying to find. To this end, three under-the-radar stocks merit a closer look as possible additions to your portfolio. In no particular order... Image source: Getty Images. It may be small now, but BigCommerce is getting big fast You've likely heard of Shopify (NYSE: SHOP), the outfit helping merchants escape the heavy-handed online marketplace operated by Amazon by building e-commerce presences of their own. What you may not know is that demand for these services is still accelerating rather than decelerating even though the bulk of the pandemic's impact is in the past. Shopify's revenue for the quarter ending in March is up 110%, spurring similar growth in operating profits. Shopify isn't the only name offering tools to companies that allow them to build their own online shopping apparatus, however. BigCommerce Holdings (NASDAQ: BIGC) is in the exact same market, boasting brands such as Gillette, Skullcandy, Ben & Jerry's, and Ivory soap as customers. It's just not as well known as Shopify mostly because of its size. BigCommerce is a $4.4 billion outfit versus Shopify's market cap of $160 billion. Don't let its smaller size fool you, though. BigCommerce is riding the same rising tide Shopify is, and it's winning over some big-name customers. Yeti Cycles and tax-software company Vertex are two of the newest additions to BigCommerce's client list, and in February the company forged a new partnership with Walmart that will enable BigCommerce customers to list their products at Walmart Marketplace. Despite these impressive deals, shares of BigCommerce are in a months-long slump. If it's replicating anything like the growth bigger rival Shopify is (which it has been up until this point), that may not be the case for much longer. Fill your plate up with SpartanNash's dividend SpartanNash (NASDAQ: SPTN) may not be a household name, but there's a good chance you or someone within your household is unknowingly a regular consumer of its products. The company is a wholesale supplier to grocery stores, as well as an owner-operator of its own brands. Last year was a huge one -- relatively speaking -- for the company. With most of the country's consumers effectively trapped at home by the COVID-19 contagion, made-at-home meals became the norm again. SpartanNash's top line improved by nearly 10% in 2020, prompting a near doubling of its operating profits. That's a tough act to follow, though, and analysts don't expect the company to do it. As of the most recent looks, the analyst community is modeling nearly a 5% sales decline in 2021, matched with a 30% slide in earnings. The top and bottom lines are expected to resume their growth again beginning in 2022, but that growth outlook is modest, as the company's past growth has been. Don't let this slow growth deter you, however. SpartanNash's bullish case is rooted in other factors. Namely, this stock's rebound from the marketwide prepandemic lull petered out in the middle of last year, barely cutting into several years' worth of price deterioration leading into that bottom and leaving the dividend yield at a healthy 4.4%. That dividend, by the way, has been paid faithfully every quarter since 2006 and raised every year since 2011. BlackLine boasts some high-profile customers Finally, add BlackLine (NASDAQ: BL) to your list of overlooked stocks worth stepping into sooner or later. Don't sweat if you've never heard of it. You're not alone. It's only a $7 billion organization, and it serves corporations rather than consumers. The company offers cloud-based accounting and finance software-as-a-service to medium-sized businesses. But what a wallop this small company packs! Last year's top line improved on 2019's revenue to the tune of 22%, and this year's sales growth projection is a healthy 17%. Next year's revenue growth is modeled to accelerate more than 20%. Though not yet profitable on a generally accepted accounting principles (GAAP) basis, operational earnings nearly tripled to $46 million on $351 million in sales. That's $0.76 per share, up from 2019's operating profit per share of $0.37. This progress was rewarded over the course of most of last year, but the stock's struggled since peaking in February. Investors may be eyeing analysts' estimates that per-share earnings will be cut in half this year and still fail to reclaim 2020's earnings levels with 2022's expected per-share profit of $0.68. Those consensus estimates may grossly underestimate the results BlackLine is positioned to produce this year and next, however. This young software outfit has been obliterating analysts' quarterly earnings estimates of late, topping most of 2019's and 2020's earnings outlooks with results two and three times more than expected -- never mind regular triple-digit earnings growth since 2016. And if that's not impressive, this will be: Coca-Cola, eBay, and Kraft Heinz are just a small sampling of BlackLine's customers. 10 stocks we like better than BlackLine, Inc.When investing geniuses David and Tom Gardner have a stock tip, it can pay to listen. After all, the newsletter they have run for over a decade, Motley Fool Stock Advisor, has tripled the market.* David and Tom just revealed what they believe are the ten best stocks for investors to buy right now… and BlackLine, Inc. wasn't one of them! That's right -- they think these 10 stocks are even better buys. See the 10 stocks *Stock Advisor returns as of February 24, 2021 John Mackey, CEO of Whole Foods Market, an Amazon subsidiary, is a member of The Motley Fool’s board of directors. James Brumley has no position in any of the stocks mentioned. The Motley Fool owns shares of and recommends Amazon, BlackLine, Inc., and Shopify. The Motley Fool recommends eBay and recommends the following options: long January 2022 $1920.0 calls on Amazon, short January 2022 $1940.0 calls on Amazon, and short June 2021 $65.0 calls on eBay. The Motley Fool has a disclosure policy.Source