What it does
Vertex supplies tax calculation, electronic invoicing, reporting and filing software for business tax teams. Its integrations connect tax work with finance and commerce systems, including SAP, Oracle, NetSuite and Shopify. The right setup depends on the taxes, markets and systems involved, with sales-led pricing.
Where Vertex fits
Vertex brings tax determination, electronic invoicing, reporting, filing and audit preparation into a connected product range. It supports sales and use tax as well as VAT and GST. This is business tax infrastructure for transactions passing through finance systems.
A quotation and an invoice behave differently
Vertex O Series exposes an application programming interface (API) for connecting another system to its tax engine. A seller sends transaction details and line items, and O Series returns calculated tax.
The message type matters:
- Quotation estimates tax on a proposed sale or rental. That estimate is not stored for reporting or remittance.
- Invoice calculates tax for the completed billing or shipping transaction and stores it for reporting.
For example, a checkout can request a quotation while a customer reviews an order, then send an invoice transaction when the sale is finalized. Integrations must distinguish those events so estimates are not treated as completed sales.
Implementation and access
The Developer Network provides calculation, transaction-management and configuration references. Your team connects the host finance system to the appropriate O Series environment and uses an access key.
O Series Online Commerce has narrower message support: quotation and invoice only, without the child-line calculations used for some complex bundled transactions.
Use Get in Touch to discuss requirements with Vertex. Its inquiry form asks for your company, country and primary application or technology provider; a public fixed-price package is not offered there.
Strengths
- Distribute Tax messages allocate tax-only adjustments among jurisdictions
- O Series provides transaction lookup and reversal functions
- Integration options cover major finance and ecommerce systems
Watch out for
- O Series Online Commerce supports fewer message types than the broader O Series service
- Online Commerce does not support nested child-line calculations
- A connected tax engine requires configuration and integration with the host system
Best for
- Business tax teams connecting indirect tax work to finance systems
- Developers integrating sales-tax calculations into order and invoice workflows
Sources
- Vertex indirect tax and compliance (Oct 27, 2026)
- Request information from Vertex (Oct 27, 2026)
- Calculate tax as a seller in Vertex O Series (Oct 27, 2026)
- O Series calculation and transaction management (Oct 27, 2026)
- Getting started with O Series APIs (Oct 27, 2026)