Three Houston companies ranked on Deloitte's annual list, with two cracking the top 100. Photo via Getty Images

Three Houston companies have made this year’s Deloitte North America Technology Fast 500 list.

The report ranks the fastest-growing technology, media, telecommunications, life sciences, fintech, and energy tech companies in North America. The Houston companies to make the list, along with their revenue growth rates from 2021-2024, include:

  • No. 16 Action1 Corp., a provider of cybersecurity software. Growth rate: 7,265 percent
  • No. 92 Cart.com, a commerce and logistics platform. Growth rate: 1,053 percent
  • No. 312 Tellihealth, a remote health care platform. Growth rate: 244 percent

“Houston’s unique blend of entrepreneurial energy and innovation continues to strengthen the local business community, and I’m thrilled to see Houston companies honored on the 2025 Deloitte Technology Fast 500 list. Congratulations to all the winners,” said Melinda Yee, managing partner in Deloitte’s Houston office.

Action1 is no stranger to lists like the Deloitte Technology Fast 500. For instance, the company ranked first among software companies and 29th overall on this year’s Inc. 5000, a list of the country’s fastest-growing private companies. Its growth rate from 2021 to 2024 reached 7,188 percent.

Mike Walters, president and co-founder of Action1, said in August that the Inc. 5000 achievement “reflects the dedication of Action1’s global team, who continue to execute against an ambitious vision: a world where cyberattacks exploiting vulnerabilities are entirely prevented across all types of devices, operating systems, and applications.”

Atlanta-based Impericus, operator of an AI-powered platform that connects health care providers with pharmaceutical and life sciences companies, topped the Deloitte list with a 2021-24 growth rate of 29,738 percent.

“Our mission is to set the standard for ethical AI-powered physician connections to pharma resources, accelerating and expanding patient access to needed treatments,” said Dr. Osama Hashmi, a dermatologist who’s co-founder and CEO of Impiricus. “As we continue to innovate quickly, we remain committed to building ethical bridges across this vital ecosystem.”

Inc. magazine has identified the fastest-growing companies in Houston. Nick Bee/Pexels

These are the 5 fastest-growing companies in Houston, according to a recent report

ready, set, grow

Bellaire-based startup Instafuel is pumping up its revenue in a big way.

Among the 250 fastest-growing companies in Texas identified by Inc. magazine, Instafuel tops the group of businesses based in the Houston metro area and ranks fifth statewide. Houston-based companies make up 68 of the state's fast-growing companies — eight Houston companies make up the top 25 list.

Instafuel, whose official corporate name is Fuel Husky LLC, provides mobile refueling services to B2B clients. The Inc. ranking, released March 13, shows Instafuel posted revenue growth of 1,353 percent from 2016 to 2018.

According to a November 2019 article published by CSP magazine, Instafuel has expanded to 30 trucks that have dispensed nearly 10 million gallons of fuel to more than 150 B2B clients in major Texas metro markets like Houston, Dallas-Fort Worth, and Austin. CSP covers the convenience and petroleum retailing industry.

"We've been bootstrapping … in stealth mode for the last four years, just trying to grow this business one [client] by one, trying to truly understand what it means to be a mobile refueler, or what we call a compact mobile refueler, and trying to target and understand the business model for small- to medium-sized business fleets," Nour Baki, vice president and co-founder of Instafuel, told the magazine.

Ranked second in the Houston area and sixth statewide by Inc. is Spring-based Bellatorum Resources LLC, whose revenue shot up 1,261 percent from 2016 to 2018. Bellatorum, a veteran-owned and veteran-operated investment company, specializes in mineral rights and oil royalty acquisitions.

"I think our work ethic and customer service is what makes us different from our competitors," Chris Bentley, president and CEO of Bellatorum Resources, told the Oil & Gas Council in July 2018.

"Based on the feedback I consistently receive from mineral owners, they tell me that many of our competitors fail to return phone calls and emails, and sometimes even fail to treat them with common courtesy and respect during their business dealings," Bentley added. "We believe in putting the mineral owner first, which always pays off for us."

At No. 3 in the Houston area and No. 8 statewide is Houston-based Sarvicus LLC. Sarvicus, an IT services and utilities provider, grew revenue by 1,048 percent from 2016 to 2018.

"Whether it's a process, piece of equipment, or a tool, we try to optimize its efficiency. When we are successful, that often translates to benefits for our customers," Sarvicus co-founder and CEO Marc Packard told CIOReview magazine.

Houston-based SIA Solutions LLC appears at No. 4 among Houston-area companies and No. 9 among Texas companies. From 2016 to 2018, revenue at the professional services engineering and consulting firm soared 1,030 percent.

"Because of our client-first philosophy, we're willing to take on tough challenges and deliver. It's in our culture. It's natural to us," CEO Srini Neralla told the McFerrin Center for Entrepreneurship at Texas A&M University's Mays Business School in November 2019. We put together strong teams comprising of firms our size or larger, including universities, in order to deliver what our clients want."

With a 2016-18 growth rate of 824 percent, Houston-based Zahroof Valves Inc. nails down the No. 5 spot among Houston-area companies and No. 14 among Texas companies. Zahroof Values makes and markets specialized valves for reciprocating gas compressors. Its investors include Saudi Aramco Energy Ventures LLC, the investment arm of oil giant Saudi Aramco.

In an August 2019 release, Zahroof Valves CEO Tony Gioffredi said: "Our commitment to driving positive change [in] the oil and gas industry is shown through our innovative products … ."

Ad Placement 300x100
Ad Placement 300x600

CultureMap Emails are Awesome

Houston hospitals win $50M grant for ibogaine addiction treatment research

ibogaine funding

The Texas Health and Human Services Commission has awarded $50 million to UTHealth Houston in collaboration with The University of Texas Medical Branch at Galveston (UTMB Health) to co-lead a multicenter research trial to evaluate the effect of ibogaine, a powerful psychoactive compound, on patients suffering from addiction, traumatic brain injury and other behavioral health conditions.

The funding will establish a two-year initiative—known as Ibogaine Medicine for PTSD, Addiction, and Cognitive Trauma (IMPACT)—and a consortium of Texas health institutions focused on clinical trials and working toward potential FDA-approved treatments.

The consoritum will also include Texas Tech University, Texas Tech University Health Sciences Center El Paso, The University of Texas at Austin, The University of Texas Health Science Center at San Antonio, The University of Texas at Tyler, The University of Texas Rio Grande Valley, Texas A&M University, The University of North Texas Health Science Center, Baylor College of Medicine and JPS Health Network in Dallas.

Ibogaine is a plant-based, psychoactive substance derived from the iboga shrub. Research suggests that the substance could be used for potential treatment for patients with traumatic brain injuries, which is a leading cause of post-traumatic stress disorders. Ibogaine has also shown potential as a treatment for addiction and other neurological conditions.

UTHealth and partners will focus on ways that ibogaine can treat addiction and associated conditions. Meanwhile, UT Austin and Baylor College of Medicine will concentrate on using it to treat traumatic brain injury, especially in veterans, according to a news release from the institutions.

The consortium will also support drug developers and teaching hospitals to conduct FDA-approved clinical trials. The Texas Health and Human Services Commission will oversee the grant program.

“This landmark clinical trial reflects our unwavering commitment to advancing research that improves lives and delivers the highest standards of care,” Dr. Melina Kibbe, UTHealth Houston president and the Alkek-Williams Distinguished Chair, said in the news release. “By joining forces with outstanding partners across our state, we are building on Texas’ tradition of innovation to ensure patients struggling with addiction and behavioral health conditions have access to the best possible outcomes. Together, we are shaping discoveries that will serve Texans and set a model for the nation.”

The consortium was authorized by the passage of Senate Bill 2308. The bill provides $50 million in state-matching funds for an ibogaine clinical trial managed by a public university in partnership with a drug company and a hospital.

“This is the first major step towards the legislature’s goal of obtaining FDA approval through clinical trials of ibogaine — a potential breakthrough medication that has brought thousands of America’s war-fighters back from the darkest parts of depression, anxiety, PTSD, and chronic addiction,” Texas Rep. Cody Harris added in the release. “I am excited to walk alongside UTHealth Houston and UTMB as these stellar institutions lead the nation in a first-of-its-kind clinical trial in the U.S.”

Recently, the University of Houston also received a $2.6 million gift from the estate of Dr. William A. Gibson to support and expand its opioid addiction research, which includes the development of a fentanyl vaccine that could block the drug's ability to enter the brain. Read more here.

Tesla no longer world's biggest EV maker as sales fall for second year

Tesla Talk

Tesla lost its crown as the world’s bestselling electric vehicle maker as a customer revolt over Elon Musk’s right-wing politics, expiring U.S. tax breaks for buyers and stiff overseas competition pushed sales down for a second year in a row.

Tesla said that it delivered 1.64 million vehicles in 2025, down 9% from a year earlier.

Chinese rival BYD, which sold 2.26 million vehicles last year, is now the biggest EV maker.

It's a stunning reversal for a car company whose rise once seemed unstoppable as it overtook traditional automakers with far more resources and helped make Musk the world's richest man. The sales drop came despite President Donald Trump's marketing effort early last year when he called a press conference to praise Musk as a “patriot” in front of Teslas lined up on the White House driveway, then announced he would be buying one, bucking presidential precedent to not endorse private company products.

For the fourth quarter, Tesla sales totaled 418,227, falling short of even the much reduced 440,000 target that analysts recently polled by FactSet had expected. Sales were hit hard by the expiration of a $7,500 tax credit for electric vehicle purchases that was phased out by the Trump administration at the end of September.

Tesla stock fell 2.6% to $438.07 on Friday.

Even with multiple issues buffeting the company, investors are betting that Tesla CEO Musk can deliver on his ambitions to make Tesla a leader in robotaxi services and get consumers to embrace humanoid robots that can perform basic tasks in homes and offices. Reflecting that optimism, the stock finished 2025 with a gain of approximately 11%.

The latest quarter was the first with sales of stripped-down versions of the Model Y and Model 3 that Musk unveiled in early October as part of an effort to revive sales. The new Model Y costs just under $40,000 while customers can buy the cheaper Model 3 for under $37,000. Those versions are expected to help Tesla compete with Chinese models in Europe and Asia.

For fourth-quarter earnings coming out in late January, analysts are expecting the company to post a 3% drop in sales and a nearly 40% drop in earnings per share, according to FactSet. Analysts expect the downward trend in sales and profits to eventually reverse itself as 2026 rolls along.

Musk said earlier last year that a “major rebound” in sales was underway, but investors were unruffled when that didn't pan out, choosing instead to focus on Musk's pivot to different parts of business. He has has been saying the future of the company lies with its driverless robotaxis service, its energy storage business and building robots for the home and factory — and much less with car sales.

Tesla started rolling out its robotaxi service in Austin in June, first with safety monitors in the cars to take over in case of trouble, then testing without them. The company hopes to roll out the service in several cities this year.

To do that successfully, it needs to take on rival Waymo, which has been operating autonomous taxis for years and has far more customers. It also will also have to contend with regulatory challenges. The company is under several federal safety investigations and other probes. In California, Tesla is at risk of temporarily losing its license to sell cars in the state after a judge there ruled it had misled customers about their safety.

“Regulatory is going to be a big issue,” said Wedbush Securities analyst Dan Ives, a well-known bull on the stock. “We're dealing with people's lives.”

Still, Ives said he expects Tesla's autonomous offerings will soon overcome any setbacks.

Musk has said he hopes software updates to his cars will enable hundreds of thousands of Tesla vehicles to operate autonomously with zero human intervention by the end of this year. The company is also planning to begin production of its AI-powered Cybercab with no steering wheel or pedals in 2026.

To keep Musk focused on the company, Tesla’s directors awarded Musk a potentially enormous new pay package that shareholders backed at the annual meeting in November.

Musk scored another huge windfall two weeks ago when the Delaware Supreme Court reversed a decision that deprived him of a $55 billion pay package that Tesla doled out in 2018.

Musk could become the world's first trillionaire later this year when he sells shares of his rocket company SpaceX to the public for the first time in what analysts expect would be a blockbuster initial public offering.

8+ can't-miss Houston business and innovation events in January

where to be

Editor's note: Kick off 2026 by hearing insightful talks and making meaningful connections in Houston's innovation scene. From networking workshops to presentations from major industry leaders, here's what not to miss and how to register. Please note: this article may be updated to include additional event listings.

Jan. 13 – Financing the Future

Hear from James Blake, head of capital markets at Fervo Energy, in this informative talk. Blake will cover the current investment landscape for geothermal power, how geothermal projects are structured and the role of policy incentives and innovative financing models in moving the industry forward. A small reception follows.

This event is Tuesday, Jan. 13, from 5:30-7:30 p.m. at the Ion. Register here.

Jan. 13 – Your Path to the Boardroom

Visit Sesh Coworking to hear from Keith Dorsey, an executive advisor and author of The Boardroom Journey, as he shares insights and lessons from hundreds of corporate board members and presents an actionable roadmap for women at every stage of their careers. Dorsey will speak on what "optimal diversity” means in the boardroom, how purpose-driven leaders sustain resilience under relentless pressure and why inclusive leadership is non-negotiable for growth and innovation.

This event is Tuesday, Jan. 13, from 6-8 p.m. at Sesh Coworking. Register here.

Jan. 14 — A Conversation with Dr. Wayne J. Riley on Leading Through Healthcare Transformation

Rice Business Partners will host Dr. Wayne J. Riley, president of SUNY Downstate Health Sciences University, for a moderated discussion with Dean Peter Rodriguez. Riley will share insights on leading complex healthcare organizations in an era of unprecedented industry challenges and reflect on his time at the Jones Graduate School of Business.

This event is Wednesday, Jan. 14, from 6:30-8:30 p.m. at McNair Hall on Rice University's campus. Register here.

Jan. 14 — VDW: Igniting Connections for Startup Success

Entrepreneurial communications instructor Diana Massaro will lead Lilie's latest Venture Development Workshop, focused on soft skills like clear communication, active listening and compelling introductions. Attendees will gain a personalized networking game plan and communication tools to turn casual encounters into meaningful relationships to support their ventures or careers.

This event is Wednesday, Jan. 14, from 6-7:30 p.m. at the Liu Idea Lab for Innovation and Entrepreneurship on Rice University's campus. Register here.

Jan. 21 — Upstream: Digital Tech Meetup

This month's Upstream: Digital Tech Meetup will explore how AI and real-time monitoring are being applied in safety-critical offshore environments, what’s working today, where the biggest gaps remain going into 2026 and how operators and service companies are approaching adoption. Expect to hear from leaders at NOV, Incom Solutions, Timbergrove and others.

This event is Wednesday, Jan. 21, from 8:30-10:30 a.m. at the Ion. Find more information here.

Jan. 22 — HEAD AND HEART: Leading Technology with Humanity While Everything Changes

Hear from Chris Hyams, former CEO of Indeed, at the latest installment of Rice's Master of Engineering Management & Leadership Seminar Series. Hyams will present on the intersection of technology, humanity and change—and how AI is reshaping all three.

This event is Thursday, Jan. 22, at 6 p.m. at Duncan Hall on Rice University's campus. Find more information here.

Jan. 22 – NASA Tech Talk

This month's NASA Tech Talks will feature a special delegation from the UK Science and Technology Network. Expect to hear from a panel of UK space experts, followed by a fireside chat featuring David Alexander, head of the Rice Space Institute, and Meganne Christian, ESA reserve astronaut and senior exploration manager.

This event is Thursday, Jan. 22, from 6-7 p.m. at the Ion. Find more information here.

Jan. 29 – Ignition Hub Startup Career Fair

Lilie will host the Ignition Hub Startup Career Fair this month in partnership with Rice University’s Center for Career Development and Career Development Office. The fair will bring together some of the most innovative, high-growth companies to offer Rice students exciting opportunities. Startups can apply to be considered for the fair. The event is open to Rice University undergraduate, graduate, MBA, and PhD students.

This event is Thursday, Jan. 29, at Grand Hall on Rice University's campus. Find more information here.

Jan. 29 – Health Policy Symposium: Value-Based Care & the Health Care Workforce

The Humana Integrated Health Systems Science Institute at the University of Houston will host its latest Health Policy Symposium this month, focused on the evolving landscape of value-based care and the importance of preparing and strengthening the health care workforce. Hear keynote addresses from leaders at Humana, UH, the American Medical Association and Houston Health Department.

This event is Thursday, Jan. 29, from 11:30 a.m.-1:30 p.m. at the Tilman J. Fertitta Family College of Medicine on Rice University's campus. Find more information here.

Jan. 30 — GHP Annual Meeting

The Greater Houston Partnership's premier event will highlight the region’s progress, honor visionary leadership and set the tone for the year ahead. Hear reflections from outgoing board chair, Gretchen Watkins (former -president of Shell USA); welcome incoming board chair, Armando Perez (EVP of H-E-B Houston); and more

This event is Friday, Jan. 30, from 11:30 a.m.-1:30 p.m. at Hilton Americas. Find more information here.