For several years, PayPal, Square, Adyen and Stripe have dominated the lucrative payments market. Now hundreds of upstarts with names like Bolt, Toast and Due are muscling into the market with their own twist on facilitating commerce between merchants and shoppers. Four years ago, the Big Four controlled 90 percent of the payments market, says Richard Crone, chief executive officer of Crone Consulting, but their share has slipped to 80 percent recently. The incumbents still generate about 54 percent of the more than $1.3 trillion in gross payment volume globally (excluding Alipay and WeChat Pay in China) and new entrants have grabbed the rest, Crone says. The upstarts\u2019 continued success depends partly on the strength of the U.S. economy; a downturn could crimp consumer spending, cutting into the fees they charge for each transaction. But for now, the new payment services are growing faster than the incumbents, Crone says. \u201cIt\u2019s the fastest growing segment of the industry after person-to-person payments,\u201d he says. The newcomers are prospering by focusing on specific industries or offering services larger rivals don\u2019t. Bolt absorbs merchants\u2019 fraud costs and claims its streamlined checkout makes shoppers less likely to abandon their purchase after filling up their carts. Toast developed technology that enables diners to order and pay from their table and lets restaurateurs monitor their operations from anywhere. Due makes invoicing easier by offering such features as payment reminders and autopay; it also offers low cross-border rates, so freelancers can get gigs in other countries. While the incumbents have many of these features, they\u2019re typically selling everything to everyone, while the smaller services can target customers more narrowly. \u201cThere\u2019s plenty of room to make a really good business, especially if you are really hyper focused,\u201d says Due Chief Executive Officer John Rampton. \u201cYou can focus on what you are really good at, and you can become the next Stripe.\u201d Due\u2019s revenue has been growing 5 percent to 6 percent month over month since it was started 3 1\/2 years ago, he says, and the company is already processing $2.5 billion in annualized payment volume from freelancers and small businesses. Bolt, which has only been around for about a year, already handles annualized payment volume of more than $1 billion, according to CEO Ryan Breslow, who says the major players took twice as long to reach that milestone. The company has raised more than $20 million from the likes of Founders Fund, whose partners include Peter Thiel, a PayPal co-founder. Many businesses are signing up with the new generation of payment processors to cut costs, better compete with Amazon.com Inc. or boost their bottom line. Invicta, a watch seller with 60 physical stores, started using Bolt for online checkout four days before Black Friday of 2017. The retailer says the number of visitors who bought something rose 30 percent, while shoppers who completed a purchase more than tripled to 32 percent. What\u2019s more, 12 percent more payments were approved than before. These are the kind of metrics a retailer would kill for, especially going into the holiday season. \u201cIt made checkout so much easier,\u201d says Ian Ankele, a user experience developer at Invicta. \u201cIt was \u2018boom boom boom, we are done.\u2019\u201d Most of the new services are focused on mobile payments, which are slowly but surely gaining traction and could become further entrenched, Crone says, as more brick-and-mortar retailers\u2014spurred on by Amazon Go cashierless stores\u2014start letting shoppers checkout with their smartphones. With their rapid growth and strong profits, the newer payment services are potential acquisition targets. In October, NCR Corp. bought JetPay, calling it \u201ca key, strategic initiative.\u201d In 2017, Ingenico Group acquired Bambora and JPMorgan Chase & Co. bought WePay. Industry watchers anticipate more acquisitions in the coming months as traditional payment processors like Worldpay Inc. and Bank of America Corp., along with the Big Four, look to buy growth or expand into different niches. Due\u2019s Rampton says he\u2019s already entertained several offers but that the price or timing wasn\u2019t optimal.\u00a0 \u201cIn the future we probably will sell to somebody,\u201d he says.