- IOSS = importing into the EU. For goods shipped from outside the EU (e.g. UK stock) to EU consumers, consignments ≤ €150. Charge EU VAT at checkout.
- OSS = selling within the EU. For goods already in the EU moving cross-border between member states (EU warehouse, Pan-EU FBA). One return instead of registering in each country.
- UK seller shipping from UK stock → IOSS. UK seller holding EU stock → OSS. Some need both.
- Marketplace sales are usually covered by the marketplace's own registration.
- UK businesses access both via an EU intermediary/registration (no EU establishment).
The core difference in one line
IOSS is for goods coming into the EU. OSS is for goods already inside the EU moving between member states.
That single distinction resolves almost all the confusion. IOSS handles the import moment (a parcel crossing the EU border); OSS handles intra-EU distance sales (stock already in the EU sold to a consumer in another EU country). Both are part of the OSS/IOSS framework.
When a UK seller needs IOSS
You need IOSS when:
- You ship goods from outside the EU (e.g. your UK warehouse) direct to EU consumers, and
- The consignments are €150 or less (see the €150 threshold).
This is the typical setup for a UK Shopify/own-store seller fulfilling EU orders from UK stock. IOSS lets you charge EU VAT at checkout so customers are not stung on delivery. You get an IOSS number via an intermediary.
When a UK seller needs OSS
You need OSS (specifically the Union OSS) when:
- You hold stock inside the EU (an EU warehouse, an EU 3PL, or Pan-European FBA), and
- You sell from that stock cross-border to consumers in other EU countries.
Without OSS you would have to VAT-register in every country you sell to; OSS lets you declare all those intra-EU distance sales through one return in a single member state. Note: OSS handles the consumer sales, but moving your own stock between EU countries (as Pan-EU FBA does) can still create separate VAT registration obligations, see FBA stock movements.
IOSS vs OSS, side by side
| IOSS | OSS (Union) | |
|---|---|---|
| Covers | Goods imported into the EU from outside | Goods already in the EU sold cross-border to EU consumers |
| Typical UK setup | Ship to EU consumers from UK stock | Hold stock in an EU warehouse / Pan-EU FBA |
| Value limit | Consignments €150 or less | No €150 cap (it is about intra-EU sales, not imports) |
| What it does | Charge EU VAT at checkout; clears customs without further VAT | Declare all intra-EU distance-sale VAT via one return |
| UK access | Via EU intermediary | Via EU registration/representation |
Some sellers need both, for example, a UK seller who ships some EU orders from UK stock (IOSS) and also holds stock in an EU FBA centre (OSS).