Jacksonville, Fla. – September 14, 2026 -- Medius has integrated Thomson Reuters ONESOURCE indirect tax determination into its AP Automation platform, allowing businesses to verify US sales and use tax on every invoice before it posts to the ERP.
Tax verification now runs inside the approval workflow before payment
As invoices move through Medius AP Automation, vendor-charged US sales and use tax is recalculated against the Thomson Reuters ONESOURCE determination engine, checking each line item jurisdiction by jurisdiction. Overcharges and undercharges are automatically flagged before payment, addressing risks for finance teams operating across thousands of US tax jurisdictions.
Incorrect tax charges create margin erosion and audit exposure
Incorrect vendor-charged tax can result in businesses paying tax they do not owe, while missed use-tax obligations can create liabilities that surface later during audits. "Overpaying taxes to vendors quietly erodes margin. Underpaying builds a liability nobody sees until an audit," said Camillo Speroni, head of partnerships and alliances, operations and technology, at Thomson Reuters. He noted businesses previously caught such errors months after the fact, whereas the new integration flags overcharges and undercharges the moment invoices land.
Partnership extends existing Medius-Pagero relationship with nearly 200 shared customers
The tax integration builds on a broader partnership between Medius and Thomson Reuters spanning tax determination and global e-invoicing compliance through ONESOURCE Pagero. Medius and ONESOURCE Pagero formed their initial partnership in 2021 and now count nearly 200 mutual customers. The ONESOURCE Pagero Network connects buyers and suppliers for automated, compliant exchange of invoices, including support for Peppol access, clearance, and e-invoicing mandate compliance across networks.
Combined platform targets compliance amid spreading e-invoicing mandates
As e-invoicing mandates expand across global markets, the combination of ONESOURCE Pagero E-Invoicing and Medius aims to keep invoices flowing compliantly without requiring businesses to reintegrate systems each time requirements change. Gary Hall, Chief Product Officer at Medius, said the goal is to catch tax errors "before it becomes a tax problem, on every invoice before it posts," while customers continue using their existing platform.
Thomson Reuters becomes first of planned tax-engine partner integrations for Medius
The integration marks the first in a series of planned Medius tax-engine partner integrations, with Thomson Reuters first to market. Medius offers an open set of APIs and dedicated development resources for third-party extensibility, with additional integrations across tax, compliance, and other financial systems to follow.