IOSS VAT charged twice: what should a UK seller do?

A buyer forwards a payment request and asks why tax is being charged again. Your shop needs to resolve the order, but first establish what the new request actually contains. Sending a parcel to the EU from the UK involves a sale record, transport booking and import declaration, and those records can disagree. This guide follows that investigation for parcels leaving Great Britain. It covers a problem on an individual order rather than the wider business choice between importing customer parcels and holding EU stock.

Is the second payment request really another VAT charge? #

Ask for an itemised assessment or invoice, the tracking reference and any payment receipt. Match the reference to your order before comparing amounts. Import VAT, customs duty and the operator’s own clearance charges perform different jobs. German customs explains that postal and courier operators may charge a separate fee for submitting declarations and advancing import charges. A customer who sees one total payment request may understandably describe all of it as tax.

Also read the checkout invoice carefully. Was the tax actually collected by your shop or by a marketplace? Which order and destination does it cover? A generic tax-inclusive message is weaker evidence than the transaction record. Keep both records together and identify the precise amount in dispute. Your support reply can then explain what you are checking, rather than sending the customer an unrelated description of Brexit shipping.

What has to happen for the IOSS import VAT exemption? #

The European Commission’s current VAT exemption guidance covers eligible business-to-consumer goods dispatched from outside the EU in consignments not exceeding €150, excluding excise goods. For the IOSS import VAT exemption, a valid IOSS number must be provided in the customs declaration. Collecting VAT at checkout is one part of the process; getting that valid identifier into the declaration is another.

Trace the handoff from the party collecting VAT to the person submitting the declaration. Ask the booking operator to confirm which IOSS data was supplied and whether it was accepted for the parcel. If a marketplace collected VAT, follow its instructions for that transaction and ask it to help trace the data. Do not substitute an unrelated seller identifier simply because it is already saved in your shipping account.

The Commission’s customs guidance says that a missing or invalid IOSS number prevents the import VAT exemption. Treat that as a specific data investigation. Find out whether the number was absent, rejected or supplied in a place that did not populate the declaration. Keep identifiers within the necessary operational correspondence. The customer needs clear case instructions and evidence of the sale, while the declarant needs the information required to investigate the customs record.

Could combining orders have pushed the parcel outside IOSS? #

Yes. The Commission’s explanatory notes discuss separate orders that are packed and dispatched together as one consignment. If the combined intrinsic value exceeds €150, using IOSS on the individual checkout transactions does not make the combined parcel eligible. In the scenario described by the Commission, VAT paid through IOSS must be reimbursed by the supplier or marketplace using evidence of the import VAT payment, with the relevant IOSS records corrected.

Check the packing record rather than only the webshop order list. Were two purchases put into the same box for the same customer? Which goods were covered by the transport reference? A fulfilment decision made after checkout may have changed what customs received. This does not mean every order arriving on the same day is one consignment. Ask the declarant to apply the official consignment definition to the actual transport arrangement.

AirPost’s live GB to DE page illustrates why combining orders can look attractive operationally. On 10 October 2026, DPD Drop Off Europe showed approximately £11.11 for both the small parcel up to 5 kg, sized 35 × 25 × 15 cm, and the medium parcel up to 10 kg, sized 45 × 35 × 30 cm. That transport pricing does not change the IOSS value limit or justify merging transactions without reviewing the resulting consignment.

The quoted rate already includes AirPost’s €0.85 platform fee; your sender’s agreed fee is separate. The pound figures are displayed conversions, and payment is in euros. Keep those transport costs out of the question of whether IOSS data was valid. Ask the operator to confirm the actual service’s IOSS handling before dispatch, since the public price listing does not establish that workflow.

Which value and invoice details should you review? #

Intrinsic value concerns the goods themselves. The Commission’s definition excludes transport and insurance when separately indicated, but includes them when embedded in the goods price without a separate indication. Review the invoice actually used for clearance alongside the amount paid and packing record. Have the declarant explain any difference between the sale value and the value recorded at import, rather than deciding eligibility from the parcel’s weight.

For a shop taking payment in pounds, retain the euro calculation used when accepting the order. The Commission recommends showing the corresponding euro goods price on the accompanying invoice to reduce exchange-rate disputes close to the threshold. Keep the date and supporting transaction record with that calculation. Changing the declared amount after a customer complains is not a substitute for correcting an identified error through the relevant operator.

The existing UK to EU commercial invoice checklist covers the broader document contents. For this investigation, focus on the fields that explain eligibility and transmission: goods value, currency, dispatch arrangement, VAT collection party and the declaration’s IOSS treatment. Read those records together; a correct invoice cannot establish that a different booking system transmitted the right data.

Who should correct or refund the payment? #

Separate a possible customs assessment error from VAT incorrectly retained at checkout. Ask the declarant about the former and the party that collected the sale VAT about the latter. The Commission’s examples for consignments that become ineligible describe the supplier or marketplace reimbursing IOSS VAT based on customs payment evidence. Follow that documented route where it applies rather than promising that every customer can reclaim every charge from customs.

1. Identify the VAT collection party on the original transaction.
2. Obtain the itemised import assessment and evidence of any payment.
3. Ask the declarant to confirm the reason IOSS was not applied.
4. Arrange the appropriate correction or reimbursement with the responsible party.
5. Match the completed refund and reporting correction to the original order.

If the parcel has not been released, promptly establish the operator’s deadline and correction options. Do not tell the customer to ignore a notice while the investigation is open. Explain what evidence you need and when you will update them. If they have already paid, save the receipt before beginning reimbursement. Keep a clear record of what remains unresolved, particularly where one invoice includes both a VAT issue and separate service charges.

Can you promise that IOSS removes every import charge? #

No. IOSS addresses the relevant VAT collection and reporting; it is not a general exemption from all import costs. The Commission’s current low-value duty guidance reflects the rules applying since July 2026. A duty line can therefore be a separate question even when VAT was properly collected through IOSS. Consult the current official guidance and the existing EU low-value duty article before calling a parcel duty-free.

Review your checkout and support wording after resolving the case. If you promise no payment at delivery, make sure the booked arrangement covers the charges that promise includes. A VAT-paid badge alone may not communicate the whole situation. Give the packing team a rule for reviewing combined orders, and make the customs data handoff part of the dispatch process rather than relying on a note added to the invoice.

Would moving the goods to EU stock avoid this order-level problem? #

AirPost’s local fulfilment arrangement lets a shop place stock with a sender near customers, who then prepares and dispatches local orders. Once properly imported and released, ordinary domestic orders from that stock do not repeat the Great Britain to EU import. The stock movement still needs a correctly arranged import, and the resulting sales need the appropriate VAT treatment.

Use the existing IOSS versus EU stock comparison for that wider decision. The immediate task here is to close the individual case accurately and fix the cause. Retain a short internal record: which data failed, who corrected it and what changed before the next dispatch. A refunded order is resolved financially; a corrected dispatch process is what helps the next customer receive the expected service.