Businesses selling through Amazon, Shopify, eBay, Kaufland or their own online store across several countries quickly encounter the terms OSS and IOSS. Both schemes simplify VAT compliance for cross-border business-to-consumer sales. They apply to different supply chains, however, and should not be confused with each other, standard import VAT, customs clearance or local VAT registrations.

In 2026, cross-border European e-commerce rules face additional updates. While the One Stop Shop (OSS) and Import One Stop Shop (IOSS) schemes have stabilized since their 2021 launch, new EU customs regulations taking effect in July 2026 impact low-value imports and platform deeming rules.

For online retailers and tax advisers, correct application of OSS and IOSS is crucial. Misapplying tax rates, missing return deadlines or failing to document stock movements between foreign FBA warehouses leads to back taxes, interest and tax penalties across multiple EU member states.

This comprehensive guide clarifies the differences between OSS and IOSS in 2026, explains the €10,000 threshold and €150 import limit, outlines filing deadlines and highlights common accounting mistakes to avoid.

Quick Comparison: OSS vs IOSS at a Glance

Parameter	One Stop Shop (OSS)	Import One Stop Shop (IOSS)
Dispatch Origin	Inside the EU (e.g. warehouse in DE, PL, CZ)	Outside the EU (e.g. supplier in China, UK, USA)
Customer Location	B2C customer in another EU member state	B2C customer in an EU member state
Goods Value Limit	No upper limit	Max €150 intrinsic value per consignment
VAT Destination Principle	Applies above €10,000 EU-wide threshold	Applies from the first euro (0 € threshold)
Filing Frequency	Quarterly (end of month following quarter)	Monthly (end of month following report month)
German Authority	Bundeszentralamt für Steuern (BZSt)	Bundeszentralamt für Steuern (BZSt)
Primary Advantage	Avoids local VAT registration in each EU country	Fast-track customs release; no import VAT at border

Section 1: One Stop Shop (OSS) Explained

The One Stop Shop (OSS) portal allows EU-established businesses selling goods to non-taxable private consumers in other EU member states (intra-Community distance sales) to report and pay destination VAT through a single electronic portal in their home country.

The €10,000 EU-wide Threshold (Section 3a(5) UStG)

Until cross-border B2C distance sales exceed €10,000 net in a calendar year across all EU member states combined (plus telecommunications and digital services), small EU businesses may apply domestic VAT rates (e.g. German 19%).

Once total EU distance sales exceed €10,000 in the current or preceding calendar year:

Destination VAT applies to every sale (e.g. 21% for Spain, 20% for France, 25% for Sweden).
The merchant must register for OSS or register locally in every destination country.

What OSS Covers:

Intra-Community distance sales of goods dispatched from an EU state to B2C customers in another EU state.
B2C services supplied to EU consumers where destination tax rules apply.

What OSS DOES NOT Cover:

B2B intra-Community sales: Requires standard zero-rated intra-Community supply reporting with valid EU VAT IDs.
Domestic B2C sales: Sales shipped from German stock to German customers stay in standard German VAT returns.
Intra-EU stock transfers (FBA cross-border storage): Shifting inventory between Amazon FBA warehouses (e.g. DE ➔ PL) remains a taxable intra-Community transfer requiring local VAT registration in Poland.

Section 2: Import One Stop Shop (IOSS) Explained

The Import One Stop Shop (IOSS) was introduced to simplify VAT collection on goods imported from non-EU countries (such as China, UK, Switzerland, Turkey) directly to B2C buyers in the EU.

Key Rules for IOSS:

€150 Intrinsic Value Limit: Applies only to consignments where the net value of goods does not exceed €150 (excluding shipping and insurance unless itemized in the price).
VAT Collected at Checkout: The merchant or marketplace collects destination EU VAT directly from the customer at the time of online sale.
Customs Fast-Track: At importation, the carrier presents the merchant's IOSS number. Import VAT is waived at the border, avoiding delivery delay and unexpected COD fees for the customer.

2026 EU Customs Reform Note:

Starting in mid-2026, the EU is phasing out the duty-free exemption for goods under €150, introducing simplified customs tariff buckets while maintaining the IOSS mechanism for streamlined VAT reporting.

Section 3: Marketplace Rules (Deemed Supplier / Fiktiver Lieferer)

When selling through electronic interfaces such as Amazon, eBay, AliExpress or Kaufland, the marketplace often acts as the deemed supplier under section 3(3a) UStG:

Non-EU Seller using EU FBA stock: If a non-EU merchant stores goods in an EU FBA warehouse and sells to an EU consumer, Amazon is deemed to buy and resell the goods. Amazon collects and reports destination VAT via OSS.
Imported Consignments ≤ €150: When facilitating imports under €150, marketplaces like Amazon or eBay automatically collect VAT under their corporate IOSS number.

Merchants must ensure their ERP or accounting interface correctly identifies marketplace-deemed transactions so revenue is not double-reported as direct merchant VAT liabilities.

Section 4: Reporting Deadlines & Payment Rules

Return Type	Reporting Period	Deadline for Filing and Payment
OSS Return (EU B2C)	Q1 (Jan – Mar)	30 April
	Q2 (Apr – Jun)	31 July
	Q3 (Jul – Sep)	31 October
	Q4 (Oct – Dec)	31 January
IOSS Return (Import B2C)	Monthly (e.g. January)	End of following month (e.g. 28/29 February)

Important: Unlike German advance VAT returns (Umsatzsteuervoranmeldung), no filing extension (Dauerfristverlängerung) exists for OSS or IOSS filings. Late filings trigger immediate automated interest penalties from the BZSt.

Section 5: Common E-Commerce OSS & IOSS Mistakes

Tax audits of e-commerce businesses consistently highlight five recurring OSS/IOSS errors:

1. Misclassifying FBA Cross-Border Inventory Transfers

Storing inventory in Amazon FBA warehouses in Poland or the Czech Republic (Central European Programme) creates mandatory local VAT registrations in PL and CZ. Shipping stock from Germany to Poland is an intra-Community transfer, NOT an OSS transaction.

2. Incorrect EU Destination VAT Rates

Applying standard VAT rates where reduced rates apply (or vice versa)—such as books, food items or children's apparel—distorts liability. In 2026, over 27 EU member states maintain varying reduced and super-reduced VAT rates.

3. Exceeding €10,000 Threshold Without Registering

Continuing to charge 19% German VAT after crossing the €10,000 threshold results in back taxes owed to foreign tax authorities while requiring formal refund applications in Germany.

4. Currency Conversion Errors

OSS returns to the BZSt must be reported in Euros (EUR) using official European Central Bank (ECB) conversion rates for the final day of the reporting period.

5. Double-Reporting Marketplace Sales

Failing to separate direct shop sales (merchant OSS liability) from Amazon/eBay marketplace sales (where the platform paid VAT) leads to double tax payment.

How KudTax Automates OSS and IOSS Accounting

Manual management of 27 EU tax rates, threshold monitoring and quarterly OSS filings in Excel is risk-prone and expensive.

KudTax simplifies OSS and IOSS VAT compliance:

Automated Destination VAT Assignment: Determines exact EU destination tax rates for every order across Shopify, Amazon, eBay and custom storefronts.
Real-Time Threshold Tracking: Monitors the €10,000 EU distance sales threshold automatically, alerting merchants before compliance boundaries are crossed.
Automated OSS & IOSS Summaries: Generates ready-to-file OSS tax reports categorized by EU country code and tax rate for easy upload to the BZSt portal.
DATEV EXTF Integration: Exports posting batches with compliant DATEV BU keys and dedicated OSS revenue accounts.

Online merchants and tax advisers can test KudTax for free to automate OSS/IOSS reporting and ensure EU tax compliance.

Official and further sources

This article provides general information for tax professionals and online merchants and does not constitute formal legal or tax advice.

OSS and IOSS 2026: Differences, VAT Thresholds and Common E-Commerce Mistakes