IOSS: who needs an IOSS number, where it goes, and why VAT gets charged twice

What you do:

1. Find who the seller is for VAT. If a marketplace takes the order and the parcel ships from outside the EU with goods worth EUR 150 or less, the marketplace is the seller for VAT. It charges the VAT if it is registered for IOSS, and you register for nothing (Art. 14a(1)Directive 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 14a, paragraph 1Click opens the article on EUR-Lex.; Explanatory Notes, question 5). If you post the parcel yourself, give the carrier the IOSS number the marketplace gives you, not your own.
2. Selling from your own shop, decide whether to use IOSS. It is optional (Art. 369m(1)Directive 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 369m, paragraph 1Click opens the article on EUR-Lex.). With IOSS, your customer pays the VAT at checkout. Without it, until 30 June 2028, the carrier collects import VAT from your customer before delivery (Art. 369yDirective 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 369yClick opens the article on EUR-Lex., Art. 369zDirective 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 369zClick opens the article on EUR-Lex.), often with a clearance fee of its own (Commission, Explanatory Notes, question 3). From 1 July 2028, without it, you owe that import VAT yourself (Council Directive (EU) 2025/1539, Art. 1(1), Art. 2(1)).
3. Based outside the EU, appoint one intermediary established in the EU. It registers you in its own EU country and receives your IOSS number (Art. 369m(1)(b)Directive 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 369m, paragraph 1, point (b)Click opens the article on EUR-Lex., Art. 369m(2)Directive 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 369m, paragraph 2Click opens the article on EUR-Lex., Art. 369q(3)Directive 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 369q, paragraph 3Click opens the article on EUR-Lex.). Based in the EU, register at home, with no intermediary. Based in Norway and shipping only from Norway, register in any EU country, with no intermediary.
4. Once registered, charge the VAT of the destination country at checkout on every order shipped from outside the EU in a parcel worth EUR 150 or less. All such sales go through IOSS, not some of them (Art. 33(b)Directive 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 33, point (b)Click opens the article on EUR-Lex., Art. 33(c)Directive 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 33, point (c)Click opens the article on EUR-Lex., Art. 369m(1)Directive 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 369m, paragraph 1Click opens the article on EUR-Lex., Art. 369nDirective 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 369nClick opens the article on EUR-Lex.).
5. Send the IOSS number to the carrier electronically with each parcel’s customs data. Do not write it on the box. A parcel whose declaration lacks a valid number pays import VAT again at the border (Art. 143(1)(ca)Directive 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 143, paragraph 1, point (ca)Click opens the article on EUR-Lex.).
6. Price in the EUR 3 customs duty per item. It applies from 1 July 2026 until 1 July 2028 to every parcel of EUR 150 or less sold to an EU consumer, IOSS or not, unless the parcel goes without IOSS and its goods claim a tariff preference in a full (H1) import declaration (Council Regulation (EU) 2026/382, Art. 2; Art. 1(24) of Delegated Regulation (EU) 2015/2446; Commission, Guidance on the temporary flat fee).
7. File one IOSS return a month and pay by the end of the next month, even in a month with no sales. Keep the records of every sale for 10 years (Art. 369sDirective 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 369sClick opens the article on EUR-Lex., Art. 369vDirective 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 369vClick opens the article on EUR-Lex., Art. 369xDirective 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 369xClick opens the article on EUR-Lex.).

What IOSS is, and what it is not

IOSS is a VAT scheme, nothing else. It covers distance sales of goods shipped from outside the EU to consumers in the EU, in consignments with an intrinsic value of EUR 150 or less. Goods subject to excise duty, such as alcohol and tobacco, are outside it at any value (Art. 369lDirective 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 369lClick opens the article on EUR-Lex.). It is open to sellers inside and outside the EU, and to marketplaces (Art. 369m(1)Directive 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 369m, paragraph 1Click opens the article on EUR-Lex.).

• IOSS is not compulsory. EU countries “shall permit” sellers to use it (Art. 369m(1)Directive 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 369m, paragraph 1Click opens the article on EUR-Lex.). If you do not, the VAT is still due, only at the border.
• IOSS is not a separate tax. It is a way of declaring the ordinary VAT of the destination country. The rate is that country’s rate for the goods.
• The IOSS number is not your VAT number. It is issued for this scheme alone and may be used “only for the purposes of this special scheme” (Art. 369q(4)Directive 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 369q, paragraph 4Click opens the article on EUR-Lex.). What a VAT number is, and who needs one, has its own page.
• The IOSS number is not an EORI number. The EORI number identifies whoever declares the parcel to customs; that is on EORI number.
• IOSS is not OSS. VAT OSS covers goods already in the EU and is declared each quarter; IOSS covers imported parcels and is declared each month. Both are on EU VAT for online sellers.

Marketplace or own shop: whose IOSS number goes to customs

The answer depends on where the customer paid, not on who posts the parcel.

Sold on a marketplace. When a marketplace, platform or portal facilitates the sale of goods imported in a consignment of EUR 150 or less, the law treats the marketplace as if it bought the goods from you and sold them to the customer itself (Art. 14a(1)Directive 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 14a, paragraph 1Click opens the article on EUR-Lex.). The marketplace charges the VAT and declares it under its own IOSS number. You need no IOSS registration for those sales. If you organise the shipping, the marketplace gives you its number to pass to the carrier.

Sold in your own shop. Your own website, with a payment provider taking the money, puts no marketplace between you and the customer. The VAT is yours. Use your own IOSS number, or none.

Both. Keep the two apart, order by order. The Commission’s guidance is plain on both mistakes:

Where the IOSS number goes

It goes into the import declaration, nowhere else. Customs grants the import VAT exemption only if the number of the seller or its intermediary has reached the customs office “at the latest upon lodging of the import declaration” (Art. 143(1)(ca)Directive 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 143, paragraph 1, point (ca)Click opens the article on EUR-Lex.). In the declaration it sits in the additional fiscal reference, data element 13 16 000 000 of Annex B to Delegated Regulation (EU) 2015/2446.

You do not lodge that declaration yourself in most cases. The carrier, post or customs agent does. So:

1. When you buy postage or book the courier, enter the IOSS number in the IOSS or tax-number field of the carrier’s electronic customs data, for every parcel to the EU worth EUR 150 or less.
2. Show the price paid by the customer in euro on the commercial invoice that travels with the parcel, and the VAT charged, per rate.
3. Give the number only to those who declare the parcel. Do not print it on the label or the box. How the postal customs form carries it is in customs declaration CN22 and CN23.

On Etsy, the IOSS number appears next to each VAT-eligible order on your Orders page, and a label bought through Etsy sends it automatically (Etsy Help, Customs Fees and Physical VAT Collection).

How the EUR 150 limit is measured

The limit is the intrinsic value of the consignment: the price of the goods themselves. Transport and insurance are left out when they are shown separately on the invoice, and so are other taxes and charges (Art. 1(48) of Delegated Regulation (EU) 2015/2446). It is checked per parcel, and an order from one seller over EUR 150 never qualifies, however it is split.

What the EUR 3 duty per item adds from 1 July 2026

The EUR 150 customs duty relief is gone. From 1 July 2026 until 1 July 2028, a customs duty of EUR 3 per item applies to a consignment worth EUR 150 or less in two cases: the parcel enters under IOSS, or it is a “postal consignment” in the legal sense (Council Regulation (EU) 2026/382, Art. 1, Art. 2 and Art. 4). A postal consignment is not a parcel sent by post: it is any consignment of EUR 150 or less sold at a distance to an EU consumer, whatever the carrier, other than one entering under IOSS and other than goods that benefit from a tariff preference (Art. 1(24) of Delegated Regulation (EU) 2015/2446).

So the EUR 3 reaches your parcel with or without IOSS; only a tariff preference claimed without IOSS, in a full (H1) import declaration, avoids it. IOSS changes who pays the VAT and when, not whether the duty is due. Who owes the duty, and what applies after 1 July 2028, is on EU de minimis.

• An item is not a piece. It is all the goods in the parcel that share one tariff classification, description and, where declared, origin (Art. 1(61) of Delegated Regulation (EU) 2015/2446). The Commission’s examples: five T-shirts pay EUR 3; a T-shirt and a watch pay EUR 6.
• The declarant owes it. With IOSS, that is normally your carrier or intermediary, acting as your indirect representative, and you share the debt (UCC Art. 77(3)Regulation (EU) No 952/2013, Union Customs CodeArticle 77, paragraph 3Click opens the article on EUR-Lex.). Why a seller outside the EU rarely declares its own parcels is on EORI number. The Commission states the duty “is not a tax on consumers” and reaches the customer only in residual cases.
• Charge it at checkout, and VAT is due on it. Under IOSS the import itself carries no VAT, so no VAT is due on the EUR 3 at the border. If you add the EUR 3 to the customer’s bill when they buy, it becomes part of the price, and your IOSS VAT is charged on it too.
• A tariff preference does not help under IOSS. Goods that would qualify for a trade preference escape the EUR 3 only when they go without IOSS and claim the preference at import in a full (H1) declaration.
• Product identifiers become mandatory on 1 November 2026. From then, the customs data of these parcels carries the goods’ product identifiers; they may be given voluntarily from 1 July 2026. Whoever declares your parcels needs them from you. Which identifiers is on EORI number.
• The Union handling fee is law, but not yet charged. It is a fee for customs processing, not a customs duty. Article 20 of Regulation (EU) 2026/2108 has applied since the Regulation entered into force, except paragraphs 1, 2 and 4. The fee itself, Article 20(2), applies from 10 days after the delegated act that sets its amount enters into force (Regulation (EU) 2026/2108, Art. 20(2), Art. 287(3)(b), Art. 287(4)). The Commission adopted that act on 21 September 2026: EUR 2 per item. It is not yet in force and not yet published in the Official Journal. As the first act setting the fee, it can enter into force only if neither the European Parliament nor the Council objects within 30 days of notification, or earlier if both say they will not object. It enters into force on the day it is published in the Official Journal (Commission Delegated Regulation C(2026)6694, Art. 1, Art. 2; Regulation (EU) 2026/2108, Art. 282(7)). The Commission’s reform page of 21 September 2026 says the fee will be introduced by 1 November 2026 (Commission, EU Customs Reform).

Why VAT gets charged twice, and how it is fixed

Your customer paid VAT at checkout, then the carrier asked for import VAT at the door. That happens when customs never saw a valid IOSS number for that parcel, or the parcel did not qualify:

• the number was not sent with the parcel’s customs data, or was mistyped;
• your own number was used on a marketplace order, or a marketplace’s number on an own-shop order;
• the parcel was worth more than EUR 150, often because two orders were packed together;
• the parcel held excise goods.

When the number is missing or invalid, customs cannot apply the exemption and collects the VAT again (Art. 143(1)(ca)Directive 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 143, paragraph 1, point (ca)Click opens the article on EUR-Lex.). What you do:

1. If the number was only lost or mistyped, give the correct one to the carrier at once. Where an error happened in sending the number, the declarant can still amend the declaration with the correct one.
2. If the customer has already paid at the door, refund the VAT you charged at checkout against proof of what they paid to customs.
3. If the parcel was over EUR 150 or held excise goods, take that sale out of your IOSS return. If the return is filed, correct it in a later return, within three years of the date the first one was due (Art. 369t(2)Directive 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 369t, paragraph 2Click opens the article on EUR-Lex.). The Commission’s notes give this refund-and-correct route only for parcels over EUR 150 and for excise goods (Explanatory Notes, questions 18, 24 and 27). For a lost or mistyped number, the official fix is step 1: the declarant amends the declaration with the correct number (question 35). No official guidance says how your IOSS return treats a sale whose number never reached customs.
4. Keep the customer’s proof of payment to customs in your records.

What happens if you do nothing

The VAT is due either way. Without IOSS, until 30 June 2028, your customer meets import VAT at the door before the parcel is handed over, often with the carrier’s clearance fee, and that can lead customers to refuse the parcel (Art. 369zDirective 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 369zClick opens the article on EUR-Lex.; Explanatory Notes, question 3). Where the carrier uses the special arrangements to collect that VAT, the country of import may charge its standard VAT rate on every such parcel, whatever the goods (Art. 369zaDirective 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 369zaClick opens the article on EUR-Lex.). From 1 July 2028 those special arrangements are deleted, and the import VAT on a parcel of EUR 150 or less sold without IOSS is owed by you, or by the marketplace treated as the seller (Council Directive (EU) 2025/1539, Art. 1(1), Art. 1(6), Art. 2(1)). A seller established outside the EU, in a country that has a VAT assistance agreement with neither the EU nor the country of import, must then appoint a tax representative in that country (new Article 201(3)). The EUR 3 per item applies with or without IOSS.

Registered for IOSS and failing at it costs more. Interest and penalties for a missing, late or wrong return are set by each EU country of destination (Implementing Reg. Art. 63bImplementing Regulation (EU) No 282/2011, VAT implementing measures (consolidated text of 14 April 2025)Article 63bClick opens the article on EUR-Lex.). A seller who persistently fails is removed from the register (Art. 369rDirective 2006/112/EC, the VAT Directive (consolidated text of 14 April 2025)Article 369rClick opens the article on EUR-Lex.), and is then barred from every EU one-stop-shop scheme, in every EU country, for two years (Implementing Reg. Art. 58bImplementing Regulation (EU) No 282/2011, VAT implementing measures (consolidated text of 14 April 2025)Article 58bClick opens the article on EUR-Lex.).

Regulation (EU) 2026/2108 (OJ 19.9.2026) repeals the Union Customs Code, Regulation (EU) No 952/2013Regulation (EU) No 952/2013, Union Customs CodeThe whole regulationClick opens the law on the EU Publications Office., and applies from 21 September 2027; the UCC articles on this page are the ones in force until then (Regulation (EU) 2026/2108, Art. 284(1), Art. 287(2)).