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Cross-Border VAT

Cross-Border E-commerce VAT, IOSS, and International Tax

14 min read2026-05-08 Reviewed by specialist accountant

Cross-border e-commerce VAT for UK sellers has been substantially restructured since Brexit. The Import One-Stop Shop (IOSS) handles low-value B2C sales into the EU. The One-Stop Shop (OSS) handles B2C sales of services and certain goods. Pan-EU FBA triggers local VAT registrations in each member state where Amazon stores inventory. C79 certificates and Postponed VAT Accounting cover UK import VAT recovery. US sales tax adds another layer for sellers reaching the nexus thresholds. And the EORI plus customs paperwork covers the post-Brexit movement of physical goods.

This overview covers the major cross-border tax issues for UK e-commerce. Each section links to a detailed companion piece.

IOSS is mandatory for low-value EU B2C sales

For consignments to EU consumers below €150, IOSS allows VAT to be collected at the point of sale rather than at the border. Without IOSS registration, every package faces import VAT plus a handling fee at delivery, creating a poor customer experience and abandoned orders. UK sellers with substantial EU consumer sales need IOSS.

IOSS in practice

  1. 1Register for IOSS through an EU intermediary (UK sellers cannot register directly post-Brexit).
  2. 2Receive an IOSS number; this is included on customs declarations on outbound packages.
  3. 3Charge EU VAT at the destination country rate at checkout.
  4. 4Submit a single monthly IOSS return and pay the collected VAT to the registration country (which then redistributes).
  5. 5No VAT collected at the EU border; package clears customs without delay.

Pan-EU FBA local VAT registrations

Pan-EU FBA places UK seller inventory in Amazon warehouses across multiple EU member states (Germany, France, Italy, Spain, Poland, Czech Republic). Each storage location triggers local VAT registration in that country, with monthly or quarterly returns and local-language compliance. Pan-EU FBA can multiply VAT registration overhead 5-7x compared to UK-only operation.

The Cross-Border VAT Series

Each piece below covers one specific cross-border tax topic in detail.

Part 1

The Import One-Stop Shop (IOSS): Registration, Compliance, and Limits for UK Sellers

IOSS lets UK sellers collect EU VAT at checkout on B2C consignments below €150, clearing them through EU customs without delay. Without IOSS, every package faces import VAT plus a courier handling fee at delivery, which is the single largest abandoned-cart driver for UK sellers shipping into Europe.

Part 2

Navigating Pan-EU FBA: Triggering Local VAT Registrations in EU Member States

Pan-EU FBA gives a UK seller faster Prime fulfilment and lower fees in exchange for a structural complication: every member state where Amazon stores inventory triggers a separate local VAT registration. Six member states means six monthly returns, six local-language compliance burdens, and registration costs that materially exceed the FBA fee savings for smaller sellers.

Part 3

Reclaiming UK Import VAT on Freight: Understanding C79 Certificates and PVA

UK e-commerce brands importing stock from China or other non-UK suppliers pay import VAT at the UK border. Two recovery routes: the paper C79 certificate or the Postponed VAT Accounting (PVA) scheme. The cash-flow difference between them runs into tens of thousands of pounds per year for a £500k stock buyer.

Part 4

US Sales Tax Nexus for UK E-commerce Brands: Economic vs Physical Triggers

US sales tax has no federal rate. Each state sets its own rules, its own threshold, and its own filing cadence. A UK Shopify or Amazon seller can trigger registration in a dozen states without ever realising the line was crossed.

C79 and Postponed VAT Accounting

When UK sellers import goods from outside the UK (typically from China or other Asian suppliers), import VAT is due at the border. Two recovery mechanisms:

  • C79 certificate: monthly summary of import VAT paid; recoverable on the next VAT return as input tax. Paper-based, slower.
  • Postponed VAT Accounting (PVA): account for import VAT directly on the VAT return rather than paying at the border. Cash-flow advantage; almost universal for high-volume importers.

US sales tax nexus

UK e-commerce brands selling to US customers face US sales tax obligations once they cross "economic nexus" thresholds (typically $100,000 in sales or 200 transactions per state, varying by state). Once nexus is triggered, registration in the relevant state, ongoing collection, and filing become mandatory. Specialist US tax software (TaxJar, Avalara) automates the multi-state compliance for serious sellers.

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