Summary
AI is reshaping software category after category in real time, but tax remains stubbornly manual: expensive partners, manual filings, and services that haven’t scaled. Numeral is well positioned to transform it. Through a powerful wedge in sales tax, Numeral has emerged as a leading next-generation provider for e-commerce businesses, SaaS, manufacturing, wholesale, and beyond. Numeral’s AI-powered service is making it possible for every business to stay compliant and access tax strategies historically reserved for the largest enterprises. We’re proud to back Sam, Matt, and the Numeral team on their $100M Series C.
- Founders: Sam Ross (CEO), Matt Duvall (CTO)
- Sector: Tax Compliance / AI Applications
- Location: San Francisco, CA
The Opportunity
Sales tax compliance is a tax on growth. Every new state a company enters, every product line it adds, and every billing model it adopts creates another jurisdiction to track and another filing deadline to manage. A mid-market e-commerce company selling across 40 states faces hundreds of distinct filing deadlines per year, each governed by jurisdiction-specific rules on taxability, rates, and remittance timing. Scale that across 13,000+ U.S. taxing jurisdictions, each with its own product-level classification rules, and the operational burden grows faster than the business itself.
Historically, companies have had two paths to manage tax: pay a Big 4 firm six figures for manual, engagement-based service, or stitch together legacy software that still requires significant human configuration and oversight. Incumbents were built in an era of static, rules-based tax software and were designed to assist tax teams, versus systems that can adapt and reason their own.
Two structural shifts are opening the door to something fundamentally different.
First, regulatory complexity is accelerating. States are moving to tax modern business models. California, for example, recently enacted a law extending sales and use tax to SaaS and electronically delivered software beginning in 2027. For companies operating across states and countries, changes like these create a constant need to monitor new obligations and update systems accordingly.
Second, AI has reached the point where it can handle the execution, not just flag the work. Tasks that used to require teams of specialists reading local tax rulings, validating exemption certificates, and classifying products across jurisdictions can now be automated with the accuracy and consistency that compliance demands. The question today is who builds the platform that earns enough trust to own it.
The Solution
Numeral gives companies a third path: an AI-native platform that handles sales tax compliance as an automated outcome, not a manual tool.
The platform covers the full compliance lifecycle. Numeral monitors nexus obligations across all 50 states, automatically registers businesses in new jurisdictions when thresholds are triggered, calculates tax at the transaction level, files returns, remits payments directly to tax authorities, and manages exemption certificates. It also supports VAT and GST compliance in more than 90 countries, connecting with over 40 billing systems, financial platforms, and ERP systems.
What makes Numeral different from prior approaches is depth of integration and scope of automation. Rather than sitting on top of existing workflows and flagging obligations for humans to act on, Numeral plugs directly into a company’s core financial stack and executes compliance end-to-end. The result is measurable: customers reduce time spent on tax filings and registrations by up to 80% and cut manual spreadsheet work and filing errors by up to 95%.
Numeral also started with the harder problem. While several next-generation competitors focused on SaaS tax, which is relatively uniform across jurisdictions, Numeral built its infrastructure for physical goods, where taxability is determined at the product and SKU level, exemption certificates add layers of complexity, and nexus can be triggered by warehouses, inventory, and field reps in addition to revenue thresholds. That decision to solve the more complex problem first has positioned Numeral to expand into manufacturing and wholesale, the two largest sales tax verticals, with product depth that SaaS-first competitors would need to rebuild from scratch to match.
The platform also improves with scale. With a 327% year-over-year increase in total transaction volume and over 80 million transactions expected through its tax engine this year, every filing, ruling, and edge case Numeral processes compounds into a cross-client knowledge layer that informs every future engagement. Numeral backs this with a guarantee: the company contractually covers penalties and interest for errors on customer filings, a commitment few competitors are willing to make.
Why We’re Backing Numeral
We invest in founders who have lived the problem they’re solving. CEO Sam Ross spent years at Airbnb on growth before building bootstrapped e-commerce businesses generating $40M+ in combined sales across 40+ states. Managing sales tax compliance as a merchant was his biggest operational headache, so he built the solution he wished had existed. CTO Matt Duvall was an early engineer at Stripe and Notion. He saw the tax problem firsthand at Stripe and brings deep financial systems expertise. Sam and Matt have assembled a strong team around them, including Fatima Husain as Chief Business Officer (ex-Airbnb, Bain), Dominic Kelly as VP of Sales (ex-Marqeta, Attentive), and a number of hungry YC founders.
Beyond the team, the category itself has the characteristics that make AI-driven disruption not just possible but inevitable. Sales tax compliance involves bounded ambiguity, repetitive decision trees, high manual labor costs, and constant throughput. That’s the exact profile where AI delivers outsized value relative to human-driven approaches. And unlike many AI categories where companies need to create new budget, this market is brownfield: businesses are already spending on tax compliance, whether through internal headcount, accounting firms, or legacy software.
The market is also far larger than the software layer alone suggests. The two largest legacy incumbents generate roughly $2.5B in combined revenue, but software in total accounts for less than 10% of the $124B global market spent on indirect tax labor and services. The vast majority of that spend sits in manual work: internal teams and external service providers doing tasks that Numeral’s platform can increasingly automate. That’s the real prize, and it’s why we see the ceiling for this business as meaningfully higher than what prior category leaders achieved.
Customer feedback from our diligence reinforced this. References consistently pointed to Numeral’s reliability, accuracy, and service quality as clear differentiators against both legacy incumbents and newer competitors, with several noting it as a product they trust enough to hand full control over their tax filings.
What’s Ahead
Looking ahead, Numeral is expanding beyond core compliance into higher-value services that today are dominated by accounting firms and Big 4 engagements: tax recovery, audit defense, AP invoice auditing, and ERP rules engines. The company is also building deeper partnerships with accounting firms through a new partner program, letting firms refer clients, resell the platform, or use it to deliver their own services.
We believe Numeral is well positioned to define the future of automated tax infrastructure, and we’re proud to partner with Sam, Matt, and the entire Numeral team as they build it!
