What is OSS/IOSS for Ecommerce?
Selling to customers in the EU from the UK has changed significantly since Brexit. One thing has not changed though: EU VAT still applies. If you sell goods online to EU consumers and do not understand how OSS (One Stop Shop) and IOSS (Import One Stop Shop) work, you could easily fall into VAT non-compliance without realising it.
The introduction of the EU VAT ecommerce reforms was designed to simplify cross-border VAT reporting. In reality, many UK sellers now find themselves unsure whether they need OSS, IOSS, local EU VAT registrations, or a mix of all three. Getting this wrong can lead to unexpected VAT bills, penalties, frozen marketplace accounts, or shipments being stopped at customs.
This post is written specifically for UK ecommerce businesses, including:
- Online retailers selling directly to EU customers
- Amazon FBA and other marketplace sellers
- Shopify, WooCommerce, and DTC ecommerce brands
- UK businesses importing goods into the EU for onward sale
We will explain what OSS and IOSS are, when you need them, and how they work in real-world ecommerce scenarios. You will also learn how to stay fully compliant with EU VAT rules while keeping admin, costs, and disruption to a minimum.
Why OSS and IOSS Matter for UK Ecommerce Sellers
Before July 2021, EU VAT compliance often meant registering for VAT in multiple EU countries. The OSS and IOSS schemes were introduced to reduce this burden by allowing sellers to submit a single VAT return covering multiple EU member states.
For UK sellers post-Brexit, these schemes are no longer optional in many cases. They are often the simplest and safest way to charge, collect, and report EU VAT correctly, especially when selling low-value goods or using fulfilment centres within the EU.
Failing to register when required can result in:
- Incorrect VAT being charged to EU customers
- Customs delays and rejected imports
- Marketplace account restrictions or suspensions
- Backdated VAT liabilities and penalties
What This Post Will Help You Do
By the end of this guide, you will:
- Understand the difference between OSS and IOSS
- Know exactly when a UK business needs to register
- See practical examples for common ecommerce models
- Learn how to stay compliant without over-registering
- Know when to seek professional VAT advice
Useful Official Resources
Throughout this guide, we will reference official guidance so you can verify rules and stay up to date:
- HMRC guidance on VAT and EU supplies after Brexit
- European Commission OSS and IOSS overview
- Registering for IOSS as a non-EU business
If you are selling into the EU or planning to expand, understanding OSS and IOSS is no longer a nice-to-have. It is a core part of running a compliant and scalable UK ecommerce business.
What Are OSS and IOSS?
OSS (One Stop Shop) and IOSS (Import One Stop Shop) are EU VAT schemes introduced to simplify how VAT is reported and paid on cross-border ecommerce sales to EU consumers.
It is important to be clear on one point early: OSS and IOSS do not remove VAT obligations. VAT is still due in the customer’s EU country. These schemes simply change where and how that VAT is declared and paid, making compliance more manageable for online sellers.
For UK businesses selling into the EU post-Brexit, OSS and IOSS are often the most practical way to remain compliant without needing multiple EU VAT registrations.
OSS (One Stop Shop)
OSS allows businesses to report and pay VAT on EU cross-border B2C sales through a single quarterly EU VAT return. Instead of registering for VAT in every EU country where customers are located, sellers submit one return via their chosen EU member state of identification.
OSS typically applies to:
- UK businesses selling goods to EU consumers where the goods are already located within the EU
- Distance sales of goods across EU borders
- Certain B2C services supplied to EU customers
The VAT rate charged is based on the customer’s country, not the seller’s location. OSS then distributes the VAT to each relevant EU tax authority on your behalf.
Key benefit: one VAT return, one payment, and significantly reduced administrative burden.
Official guidance: European Commission OSS overview
IOSS (Import One Stop Shop)
IOSS is designed specifically for low-value goods imported into the EU with a consignment value of €150 or less. It applies where goods are shipped directly to EU consumers from outside the EU, including from the UK.
Under IOSS:
- VAT is charged to the customer at checkout
- The seller declares and pays VAT via a monthly IOSS return
- Goods can clear EU customs without VAT being charged on delivery
This creates a smoother customer experience by avoiding unexpected courier charges, delivery delays, and refused parcels.
Most UK businesses must appoint an EU-based IOSS intermediary to use the scheme, unless selling through a marketplace that assumes VAT responsibility.
Official guidance: HMRC guidance on registering for IOSS
Quick Practical Tip for UK Sellers
If you sell goods priced under €150 directly to EU customers from the UK, IOSS is usually the cleanest solution. If your goods are stored in the EU or sold cross-border within the EU, OSS is more likely to apply. Many ecommerce businesses end up using both schemes depending on their fulfilment model.
Understanding which scheme applies to each sales channel is essential to avoid underpaying VAT or registering where you do not need to.
Why OSS and IOSS Matter for UK Ecommerce Businesses
Since Brexit, the UK is treated as a non-EU country for VAT purposes. This means UK ecommerce businesses selling to EU consumers must now follow EU import VAT and distance selling rules, even if they only sell online and have no physical presence in the EU.
In practice, this catches many sellers out. VAT obligations do not disappear just because your business is UK-based. If you sell goods to EU customers, VAT compliance becomes part of the sales process whether you plan for it or not.
The VAT Challenges UK Sellers Commonly Face
Without the correct VAT setup, UK ecommerce businesses may encounter:
- Import VAT at the EU border when goods enter the EU
- EU VAT charged at the customer’s local rate, not the UK rate
- Marketplace VAT rules imposed by platforms such as Amazon, Etsy, and eBay
- Courier handling fees and delivery delays passed on to customers
These issues often result in abandoned carts, customer complaints, refused deliveries, and in some cases, frozen marketplace accounts.
How OSS and IOSS Help in Practice
Using OSS and IOSS correctly does not remove VAT, but it makes the process predictable, transparent, and manageable for both sellers and customers.
When set up properly, these schemes help UK ecommerce businesses:
- Improve customer experience by showing VAT clearly at checkout
- Avoid double VAT charges at the border and on delivery
- Speed up deliveries by reducing customs friction
- Reduce the number of EU VAT registrations needed
- Protect marketplace seller accounts by staying compliant with platform rules
Why Marketplaces Care So Much About VAT Compliance
Online marketplaces are now legally responsible for VAT in many scenarios. As a result, platforms actively monitor seller VAT compliance and may restrict listings or suspend accounts if VAT numbers or OSS and IOSS details are missing or incorrect.
You can see how seriously this is treated in official guidance:
Key Takeaway for UK Ecommerce Businesses
If you sell to EU consumers, OSS and IOSS are no longer optional concepts to understand later. They directly affect pricing, delivery times, customer satisfaction, and your ability to trade on major marketplaces. Getting them right early is far cheaper and less stressful than fixing problems after VAT authorities or platforms get involved.
OSS Explained in Detail
The One Stop Shop (OSS) scheme is split into two distinct versions: Union OSS and Non-Union OSS. Which one applies depends on where your business is established, where your goods or services are supplied from, and whether you are selling goods or services.
Union OSS
Union OSS is the version most relevant to ecommerce businesses selling physical goods within the EU.
Union OSS is used by:
- EU-established sellers
- UK sellers who hold stock within the EU, such as goods stored in Amazon FBA or third-party fulfilment warehouses
Union OSS covers:
- B2C sales of goods between EU member states
- Certain B2C services supplied within the EU
If your goods are already located in one EU country and you sell to consumers in other EU member states, Union OSS is usually required. Without it, you would typically need separate VAT registrations in each EU country where customers are based.
Common real-world example: A UK business stores products in Germany using Amazon FBA and sells to customers in France, Spain, and Italy. Union OSS allows the seller to report all EU VAT due through a single quarterly OSS return instead of registering in multiple countries.
Official reference: European Commission guidance on Union OSS
Non-Union OSS
Non-Union OSS applies to businesses established outside the EU, including the UK, but it only covers B2C services, not goods.
Non-Union OSS applies where a non-EU business supplies services to EU consumers, such as:
- Digital services
- Online platforms
- Streaming services
- Downloadable products and subscriptions
Most UK ecommerce businesses selling physical products do not use Non-Union OSS unless they also sell digital or electronically supplied services alongside their goods.
Practical tip: If your business sells both physical products and digital services, you may need Union OSS or IOSS for goods and Non-Union OSS for services. This is an area where tailored VAT advice is strongly recommended.
Official reference: European Commission guidance on Non-Union OSS
IOSS Explained in Detail
The Import One Stop Shop (IOSS) is designed specifically for low-value goods imported into the EU. It simplifies VAT collection where goods are shipped directly to EU consumers from outside the EU, including from the UK.
IOSS applies when all of the following conditions are met:
- The goods are sold B2C
- The goods are dispatched from outside the EU
- The intrinsic value of the consignment is €150 or less
How IOSS Works in Practice
- VAT is charged to the customer at checkout based on their EU country
- The seller reports and pays VAT through a monthly IOSS return
- Goods clear EU customs without VAT being charged on import
- Customers receive their goods without unexpected delivery fees
This process removes friction at the border and creates a far better customer experience. Shoppers are much more likely to complete a purchase when VAT is clearly included upfront and deliveries arrive without delays or additional charges.
Conversion tip: Many UK ecommerce businesses see improved conversion rates and fewer refused deliveries once IOSS is implemented correctly, especially for lower-value products.
Most UK sellers must appoint an EU-based IOSS intermediary unless they sell exclusively through a marketplace that takes responsibility for VAT collection.
Official reference: HMRC guidance on IOSS registration










