OSS — One Stop Shop for Amazon Sellers — with CountX

Navigating the European VAT landscape has never been a simple task for Amazon sellers, but the introduction of the One-Stop-Shop (OSS) on July 1, 2021, added a layer of both simplification and significant risk. While the EU marketed OSS as the ultimate solution for cross-border distance selling, the reality for Pan-European FBA (Fullfillment by Amazon) sellers is far more complex. In this session, Christian Kelm discusses the mechanics of OSS with the experts at CountX, unpacking why "One Stop" rarely means "Only One Registration" for active Amazon merchants leveraging Amazon’s sprawling logistics network across the DACH region and beyond.

The OSS Fundamentals: Simplification for Distance Selling

The One-Stop-Shop was designed to replace the previous system of individual country-specific distance selling thresholds (which ranged from €35,000 to €100,000). Under the current rules, a single EU-wide threshold of €10,000 (net) applies. Once a seller’s total B2C cross-border sales within the EU exceed this €10,000 mark, they must charge the VAT rate of the destination country.

The OSS scheme allows a seller to report and pay all this destination-based VAT via a single quarterly filing in their home country—for German sellers, this is handled through the Federal Central Tax Office (BZSt). However, as CountX emphasizes, OSS only covers the "sale" component of cross-border B2C transactions where the goods start in one EU country and end in another. It does not address the logistical reality of where those goods were stored before the sale occurred.

The Pan-EU Paradox: Why OSS is Not Enough

The most common misconception among new and mid-sized Amazon sellers is that an OSS registration replaces the need for local VAT IDs in Poland, the Czech Republic, France, Italy, or Spain. This is a dangerous fallacy. Amazon’s Pan-EU program thrives on "commingling" and "pre-positioning" inventory. When you enable Pan-EU, you authorize Amazon to move your stock across their warehouse network to ensure one-day or same-day delivery to the end customer.

The moment a single unit of your stock crosses a border to be stored in a warehouse (e.g., transported from a German fulfillment center to Wroclaw, Poland), a taxable event is triggered. OSS specifically excludes the reporting of local storage and the movement of own assets between warehouses. Therefore, if you use Amazon’s "Central Europe Program" (storage in DE, PL, and CZ) or the full Pan-EU suite (adding FR, IT, ES), you legally require local VAT registrations in every single one of those countries, regardless of your OSS status.

The €10,000 Threshold and Micro-Sellers

For small-scale German sellers just starting, the €10,000 threshold offers a brief window of simplicity. If your total intra-community distance sales stay below this amount annually, you can apply German VAT (19% or 7%) to all EU sales and report them via your standard German Umsatzsteuer-Voranmeldung.

However, CountX notes that for any serious Amazon seller, this threshold is reached incredibly quickly. Once breached, the seller must choose: either register for VAT in every single EU country they ship to (the old, expensive way) or register for OSS. Most choose OSS for the sales reporting, but they often forget that the "Storage" trigger mentioned by Christian Kelm and the CountX team operates independently of this €10,000 threshold. If you store one iPhone case in a Polish warehouse, you need a Polish VAT ID from Euro 1 of storage, even if your total EU sales are only €500.

Moving Stock: Proforma Invoices and Intra-Community Transfers

When Amazon moves your stock from Germany to a warehouse in Spain, this isn't a "sale" to a customer, but it is an "intra-community transfer." In the eyes of tax authorities, you are "selling" the goods to yourself across a border. This requires a proforma invoice to document the movement of goods.

These movements must be reported in your VAT filings in both the departure country (as a tax-exempt intra-community transfer) and the arrival country (as an intra-community acquisition). OSS cannot process these movements. This is precisely why a seller using Pan-EU logistics still needs a local tax consultant or a specialized VAT service provider to file monthly or quarterly returns in PL, CZ, FR, IT, and ES, even if they use OSS to pay the actual sales tax.

The BZSt Portal: Mechanics of OSS Filing in Germany

For a German-based GmbH or Einzelunternehmen, the OSS return is filed electronically via the BOP (BZStOnline-Portal). These filings are quarterly, due by the end of the month following the quarter (e.g., Q1 is due by April 30th).

Accuracy is paramount. The data fed into the BZSt portal must be broken down by the country of consumption and the applicable VAT rate. If you sold to 26 different EU countries, your OSS filing will have at least 26 line items. If a country has multiple rates (like France’s 20%, 10%, 5.5%, and 2.1%), your filing becomes even more granular. CountX points out that manual entry is virtually impossible for active sellers; you need an automated data bridge that pulls transaction reports from Amazon’s Merchant Token and formats them for the BZSt XML upload.

Amazon VAT Calculation Service (VCS) and OSS Integration

Amazon’s VAT Calculation Service (VCS) is a powerful tool, but it is a "dumb" system in that it only acts on the data and permissions you provide. If you tell Amazon you are OSS-registered, their system will start applying destination VAT rates to your invoices.

The friction occurs when a seller has VCS enabled but hasn't correctly configured their "Tax Registration Numbers" in Seller Central. If Amazon’s algorithm detects you are shipping from a warehouse where you haven't provided a VAT ID, it may default to a tax treatment that creates a liability for you. CountX advises that sellers must ensure their VCS settings perfectly mirror their actual tax registrations. If you are using OSS, you must indicate the "Tax Graduation" correctly in the settings to ensure Amazon doesn't incorrectly calculate tax on domestic sales (which still go into the local VAT return, not OSS).

The Hidden Complexity: Intrastat and Recapitulative Statements

While OSS simplifies the B2C delivery side, it does nothing to alleviate the burden of Intrastat reporting. Many sellers ignore Intrastat until they receive a stern letter from the Statistisches Bundesamt (Destatis).

Intrastat obligations are triggered when the value of goods moved across borders exceeds certain thresholds—in Germany, this is typically €500,000 for arrivals and €800,000 for dispatches. In other countries like Poland or Hungary, these thresholds are much lower (often around €50,000 to €100,000). Because Pan-EU inventory moves constantly, a high-volume seller can easily trigger Intrastat obligations in five different countries simultaneously. These are statistical filings, not tax filings, but the penalties for non-compliance are significant and separate from VAT penalties.

Consequences of Incorrect OSS Application

What happens if a seller wrongly applies OSS to inventory that was sold from a local warehouse? For example, if a German seller stores goods in France and sells to a French customer, that is a domestic French sale. It should be reported in the local French VAT return at 20%, not in the German OSS filing.

If this is filed incorrectly through OSS, the French tax authorities (DGFiP) will view it as unpaid tax in France. Meanwhile, you have technically overpaid tax in Germany via OSS. Correcting this involves "de-registering" the transaction from the OSS return (which can only be done through corrective filings) and paying the tax, plus late interest and penalties, in France. CountX warns that tax authorities across the EU are increasingly using automated tools to cross-reference Amazon’s "VAT Transaction Reports" (which Amazon shares with authorities) against OSS filings. Discrepancies lead to automated audits.

Benchmarking Costs: The Price of Compliance

Compliance is a cost of doing business on Amazon, and undercutting this budget is a frequent cause of business failure. For a seller utilizing the full Pan-EU program (7+ countries), the costs are generally consistent across the major specialized providers like CountX, hellotax, or AVASK.

A typical fee structure looks like this:

• Local VAT Registrations: €500–€1,000 per country (one-time).
• Monthly/Quarterly Filings: €150–€250 per country, per month.
• OSS Filing: €100–€300 per quarter.
• Fiscal Representation (if required): €500–€1,500 annually.

In total, a compliant Pan-EU seller should budget between €2,500 and €6,000 per year for VAT compliance. While this seems high, the alternative—retroactive tax assessments, frozen Amazon accounts, and 10-20% penalties on gross turnover—is far more expensive.

Checklist for DACH Sellers Expanding via Pan-EU

Before flipping the switch on Pan-EU storage, the discussion highlights several "must-haves" for German sellers. First, ensure you have a valid EORI number assigned by German customs. Second, verify your VerpackG (LUCID) registrations not just in Germany, but also in France (via ADEME) and Spain, as environmental compliance is now linked to your ability to sell in those markets.

Finally, ensure your accountancy software (like Datev, Lexoffice, or SevDesk) is compatible with your VAT service provider’s data. The bridge between Amazon’s raw API data, the OSS filing, and your local Buchhaltung is where most errors occur. Specialized middleware or using a provider like CountX that handles the data end-to-end is often the only way to remain audit-proof.

This article is based on the AMALYZE AMA Session with CountX and hosted by Christian Kelm. You can find the full video discussion on the AMALYZE YouTube channel to dive deeper into the technical nuances of European tax law for Amazon sellers.