TL;DR
  • An IOSS intermediary is an EU-established firm that registers you for IOSS and acts as your EU fiscal representative.
  • Mandatory for UK sellers: post-Brexit, UK businesses lack the EU establishment IOSS requires, so an intermediary is the only route in.
  • They provide your IOSS number, file the monthly return, remit the VAT, and share legal responsibility.
  • Providers: Eurora, Taxually, hellotax, Avalara. Cost ~£600-£1,500/year plus per-transaction fees.
  • Only needed for your own-store sub-€150 EU sales, marketplaces use their own IOSS.

What is an IOSS intermediary?

An IOSS intermediary is an EU-established business that registers a non-EU seller for the EU's Import One Stop Shop scheme and acts as that seller's fiscal representative in the EU. Think of them as your authorised EU agent for IOSS: the scheme legally requires a non-EU seller to have one.

Why an intermediary is mandatory for UK sellers

IOSS registration requires an EU place of establishment. Before Brexit a UK business was inside the EU and could register directly. Now, a UK-established business has no EU establishment, so it cannot register for IOSS on its own. The EU's solution is the intermediary: a UK seller appoints an EU-established intermediary who registers and represents them.

This is not optional, it is how the scheme works for non-EU sellers. If you want your own IOSS number as a UK seller, you must go through an intermediary. (If you do not want the cost, the alternatives are letting EU customers pay on delivery, or selling via a marketplace whose own IOSS covers it.)

What an IOSS intermediary does

Providers and typical cost

The established IOSS intermediary providers for UK sellers include Eurora, Taxually, hellotax and Avalara. Pricing models vary, but typically:

Cost elementTypical range
Annual registration + representation~£600-£1,500/year
Per-transaction or per-filing feeVaries by provider and volume
Setup / onboardingSometimes a one-off fee

Because the intermediary shares liability, expect onboarding checks. Compare providers on total cost at your transaction volume, not just the headline annual fee. An ecommerce accountant can advise whether IOSS via an intermediary is worth it for your EU volume, or whether to route EU sales another way.