Landlines are ever-so-slowly going the way of the dodo, but a few holdouts remain. Almost 43 percent of U.S. households still pay for telephone service over copper wire, according to the U.S. Center for Disease Control National Health Information Survey’s most recent findings. The same goes for the nearly 200 million companies with business phone numbers in the U.S.

That puts texting addicts in a rather awkward position, but Zipwhip is offering a solution to bridge the gap. The Seattle startup, which was cofounded by John Lauer, John Larson, and Anthony Riemma in 2007, lets people with smartphones send messages to landlines, VoIP, and toll-free numbers hassle-free, as they would to mobile handsets. Now, with over 100 enterprises, 10,000 direct customers, and more than 30,000 businesses tapping its text-to-landline platform, the company is gearing up for its next stage of growth.

Zipwhip today announced it has raised $51.5 million in a Series D round led by Goldman Sachs’ Private Capital Investing group, with participation from existing investors — including OpenView, Microsoft’s M12, and Voyager Capital. This follows a $22.5 million Series C investment round in September 2017 and a $14 million Series B in 2016 and brings the firm’s total raised to $92.5 million.

The fresh capital will be used to propel Zipwhip toward its goal of “text-enabling” every organization in North America, said Lauer — who serves as CEO — chiefly by investing in product development and “substantially” growing the engineering and leadership teams. The company has already laid a solid foundation: Zipwhip’s 3.3 million text-enabled phone numbers saw message volume increase by 262 percent, which drove three-year revenue growth of 818 percent and allowed it to expand its workforce to 260 people.

In November, Deloitte named Zipwhip the 137th fastest-growing technology company in North America. That puts it ahead of competitors like TextUs and just behind giants like Salesforce’s LiveMessage.

“Zipwhip is the definition of a 10-year overnight success. Over the last decade, we’ve grown, evolved, then grown some more as we carve out our place as the definitive leader of texting for business,” Lauer said. “This funding allows us to continue to evolve and expand our product suite, reach new customers in new industries, and educate the country — and the world — about the power of texting.”

Zipwhip’s eponymous cloud-based product works by intercepting, in a sense, a fraction of the more than 150 million text messages sent to landlines in the U.S. every day. They’re funneled into a Slack-like switchboard on the web, desktop, iOS, and Android that contains editable fields for names, email addresses, home addresses, and notes. Zipwhip’s clients, working either in teams or individually, can read and respond to messages inline, or set up things like message signatures and automatic replies.

In the coming months, Zipwhip plans to introduce new “enterprise-grade” software and API capabilities and to pursue partnerships with third-party services, in addition to its existing integrations with Zappier, Zoho, HubSpot, Microsoft Dynamics 365, Bullhorn, Veolicty, and others.

Last year saw the rollout of Zipwhip 2.0, which introduced features like message templates, scheduled texts, and group text, along with conversation filters, MMS, and an emoji keyboard. In September, Zipwhip launched rich communication services (RCS) support, which lets users share their location, view typing indicators, receive read receipts, make payments, reply to inline suggested buttons within native texting apps, and more.

“Zipwhip sits at the powerful intersection of a huge addressable market, [with] a proven history in industry innovation and an agile SaaS-based approach that will allow the company to grow and evolve for the foreseeable future,” said Hillel Moerman, head of Goldman Sachs’ Private Capital Investing group. “The product, team, and corporate vision behind Zipwhip position the company to continue its successful trajectory. We look forward to working with Zipwhip’s leadership team as they meet the growing demand for a better way for businesses and consumers to communicate.”

Service starts at $35 per month for basic texting. Zipwhip’s business tier, which adds unlimited landline, VoIP, and toll-free texting, plus group testing, scheduled messages, and auto-reply, jumps up to $100 per month. For larger organizations, there’s an Enterprise plan with volume-based pricing.

“Zipwhip may have created the business texting industry, but we haven’t stopped there. We plan to remain at the forefront of innovation as modern communication needs evolve,” Lauer said. “The simple fact is that people want to text. Zipwhip’s continued growth … [will] reaffirm this demand and motivate our team to deliver the next generation of business-to-consumer communication.”

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