- An IOSS number lets you charge EU VAT at checkout on consignments of goods €150 or under, so EU buyers get a clean landed price with no surprise on delivery.
- UK sellers cannot register directly (IOSS needs an EU establishment), you go through an EU-based intermediary who provides the number and files the returns.
- Format: IM + 10 digits.
- You only need your own IOSS for direct/own-store (e.g. Shopify) sub-€150 EU sales; marketplaces (Amazon, eBay, Etsy) use their own.
- Above €150, IOSS does not apply, normal import VAT + duty on delivery. See the €150 threshold.
What is an IOSS number?
An IOSS number is the VAT identification number issued under the EU's Import One Stop Shop scheme. It lets you charge EU VAT at the point of sale on consignments of goods with an intrinsic value of €150 or less shipped into the EU.
The benefit is a clean customer experience: with a valid IOSS number in the customs data, the parcel clears EU customs without VAT being charged again on delivery. Without it, the EU buyer is hit with import VAT plus a carrier handling fee when the parcel arrives, a common cause of refused deliveries and bad reviews. IOSS is part of the wider OSS/IOSS framework.
How UK sellers get an IOSS number
This is the key constraint: UK-established businesses cannot register for IOSS directly, because the scheme requires an EU place of establishment. So UK sellers register through an EU-established IOSS intermediary. The intermediary:
- Registers you for IOSS in an EU member state and provides the IOSS number.
- Files the monthly IOSS VAT return covering your EU sales.
- Acts as your EU fiscal representative, sharing responsibility for the VAT.
Providers include Eurora, Taxually, hellotax and Avalara. Cost is typically £600-£1,500/year plus a per-transaction fee. The intermediary route is the whole topic of the IOSS intermediary guide.
What an IOSS number looks like
An IOSS number is formatted as IM followed by 10 digits (for example IM0123456789). It is not the same as a normal EU VAT number, it is specific to the IOSS scheme.
You provide it to your carrier or in your customs data so it travels with the parcel; you do not print it on the customer-facing invoice, since it is confidential to you and your intermediary (exposing it risks misuse by others shipping under your number).
When you actually need your own IOSS number
You need your own IOSS number only in this situation:
- You sell direct to EU consumers (your own store, e.g. Shopify or WooCommerce), and
- The consignments are €150 or less, and
- You want to charge EU VAT at checkout rather than leave customers to pay on delivery.
You do not need your own IOSS number if you sell via marketplaces, Amazon, eBay and Etsy use their own IOSS registration for sub-€150 EU sales. And IOSS does not apply at all to consignments over €150 (see the €150 threshold) or to B2B sales. If your EU consumer revenue via your own store is modest, weigh the £600-£1,500/year cost against simply letting customers pay on delivery or routing EU sales through a marketplace.