If you searched for this expecting a European cousin of US duty drawback, stop here first: it is not that. Duty drawback refunds duty you already paid, after the goods have left the country again. Inward Processing and Outward Processing work the other way round: they suspend or reduce the duty at the point of import or export in the first place, so in the ordinary case, nothing is paid that then needs reclaiming. Confusing the two leads to businesses either overpaying and never claiming it back, or assuming a refund exists in a system that runs on suspension instead.
What Inward Processing actually is
Inward Processing (IP) lets a business bring goods from outside the customs territory, whether that is the EU or the UK, into the country to be processed, manufactured or repaired, with import duty and import VAT suspended for as long as the goods stay under the procedure. The relief is conditional: it applies provided the resulting processed products are re-exported, or another end use the authorisation covers is actually met. If the goods, or the products made from them, end up staying in free circulation instead, duty and import VAT become payable, sometimes at a lower rate if the finished product has a more favourable tariff classification than the raw materials that went in.
The European Commission's own description is direct about this: Inward Processing "permits the import of goods for working and subsequent re-export," with relief covering import duty, VAT, excise duty and commercial policy measures while the goods remain under the procedure. HMRC's UK guidance frames the same mechanism as needing "no Customs Duty and import VAT on goods that you import from outside the UK and then re-export."
Authorisation, and the economic test in principle
Neither system lets you simply start. In the UK, a business applying for full authorisation is told to apply at least a month before it starts importing, because HMRC needs that time to process the application. A lighter route, authorisation by declaration, exists for occasional use: up to 10 times in a rolling year, for goods valued up to 500,000 pounds sterling per import, without advance approval. A retrospective authorisation can also cover processing already carried out, looking back up to 12 months, or only 3 months where the goods are classed as sensitive.
Every UK application has to specify an "economic code," the category the processing operation falls into, and HMRC states plainly that an authorisation can be examined "to make sure it does not disadvantage UK producers," with amendment or cancellation possible if it is found to. That is the economic test in substance: IP exists to let processing happen that would not otherwise be commercially viable, not to let imported inputs quietly undercut domestic suppliers of the same goods. In the EU, the equivalent requirement sits inside the authorisation itself, granted by the customs authority in the member state where the business is established (with the EU-establishment condition waived only in exceptional cases), and it too can be refused or limited on the same underlying logic.
Discharge: the bill you eventually have to settle
IP is not permanent and it is not self-closing. Every authorisation carries a period within which the procedure must be "discharged," meaning the goods are re-exported, released to free circulation with duty paid, transferred to another authorisation holder, or destroyed under supervision. In the UK, a business using authorisation by declaration discharges each movement with a bill of discharge on form BOD3, due no later than 30 days after the end of that discharge period. The form has to show, among other things, the import entry details, the rate of yield, how the goods were actually disposed of, and the valuation method used. Your authorisation letter names a supervising office to contact if you need more time; HMRC's own guidance does not commit to a fixed number of extra days, so do not assume one and ask early if a deadline is going to slip.
This is also where the administrative cost of IP becomes real rather than theoretical. Records covering the full movement of the goods, marks, transfers, tariff changes, yield calculations, the lot, generally have to be kept for 4 years under the standard UK procedure. That is a meaningful ongoing commitment for a business that processes small or irregular volumes, and it is worth being honest about it: a fair amount of eligible processing never goes through IP at all, because the duty saved does not obviously clear the bar of running a compliance record that has to survive an HMRC check years later. If your processing volumes are small or occasional, weigh the relief against that cost before applying, rather than assuming the paperwork will sort itself out once the authorisation is in hand.
Outward Processing: the mirror procedure
Outward Processing (OP) runs in the opposite direction. Goods that already have EU or UK origin, or are already in free circulation there, are exported temporarily for processing or repair somewhere outside the territory, then re-imported. The point of OP is that duty on the re-imported product is not charged on its full value: it is charged only on the value added by the work done abroad, not on the value of the EU- or UK-origin materials that were already duty-paid or duty-free before they left. The European Commission's guidance is explicit that businesses using OP can "take advantage of benefits such as lower labour costs or specific technical expertise" outside the customs territory, while still only paying duty on what happened abroad rather than the whole re-imported item.
HMRC's own worked example shows how the ratio behind that calculation, the "rate of yield," is meant to work: a simple repair has a 1:1 yield, but where "500 yards of material are exported to manufacture 100 dresses, the rate of yield will be 5:1." That figure feeds directly into how much of the re-imported value is treated as new, foreign-added value for duty purposes, rather than value the exporting country already accounted for.
Authorisation works the same way as for IP, in reverse. UK full authorisation asks for at least 30 days' notice before export starts; authorisation by declaration is capped at 10 uses in a rolling year and is available for repairs only; retrospective authorisation reaches back up to 12 months, or 3 months for sensitive goods. You do not have to own the goods being exported, or be the one who re-imports them, provided you have the owner's or importer's permission.
One case gets full relief rather than partial relief: a genuinely free repair. Where goods are repaired under warranty, or because of a manufacturing defect, and no charge is made for the work, HMRC's guidance is that customs duty and import VAT are relieved in full. The moment a service charge or warranty fee is billed for that repair, duty and import VAT become due on that charge, and any replacement part supplied still has import VAT charged on its full value even where duty relief applies.
Where these procedures actually get used
Three patterns come up repeatedly in official guidance and industry practice:
- Machinery sent overseas and returned. Industrial equipment shipped out for a repair or overhaul that is not economically available at home, then brought back, is the textbook OP case: relief covers the value of the repair, not the machine's full re-import value.
- Aircraft and engine parts sent for maintenance. HMRC specifically flags simplified procedures for "the construction or repair of aircraft" and for manufacturing aircraft parts, satellites and ground station equipment, reflecting how routine it is for aviation maintenance to cross a customs border and come back.
- Garment cut-make-trim (CMT) arrangements. Fabric exported for cutting, sewing and finishing abroad, with the finished garments re-imported, is close to HMRC's own dress example above: the exporting business already owns the fabric, and duty relief is meant to apply to the labour value added abroad, not the fabric it already accounted for.
Why a plain temporary export for repair is not the same thing
It is worth being precise about what OP is not. If goods are simply going abroad briefly and coming back unchanged, unused and unaltered, that is closer to the territory covered by an ATA carnet, which exists for goods leaving and returning without any processing happening to them at all. In fact, ATA carnet rules go further than just being a different document: a carnet specifically excludes goods "intended to be processed or repaired," permitting only incidental fixes needed to keep the goods working during the trip itself. Deliberately sending goods abroad to be repaired is exactly the case a carnet will not cover, and it is exactly the case OP exists for instead. If your goods are coming back changed, whether repaired, processed or manufactured into something new, you need a duty procedure built for that change, not a temporary-admission document built for goods that never do.
UK and EU: the same names, two separate systems
Since the UK left the EU customs union, Inward Processing and Outward Processing in the UK and in the EU are administered entirely separately, by HMRC and by each member state's own customs authority respectively, even though the underlying mechanics and the terminology are close cousins. As of September 2026, HMRC's current guidance calls the procedures Inward Processing (IP) and Outward Processing (OP); the older labels, Inward Processing Relief (IPR) and Outward Processing Relief (OPR), are still in wide informal use and still appear in older HMRC notices, but they describe the same current procedures rather than something that has since been replaced. Do not assume a UK authorisation covers EU movements, or the reverse: an EU-established business needs its own EU member state authorisation, and a UK business needs a separate UK one, even for a supply chain that used to run under a single authorisation before Brexit.
How this compares with US duty drawback
| Feature | Inward / Outward Processing (EU, UK) | Duty drawback (US) |
|---|---|---|
| When duty is affected | Suspended or reduced at import or export, before it is fully paid | Paid in full first, then refunded after export |
| Authorisation | Required in advance (full, by declaration, or retrospective) | Filed per claim, within a set filing window after export |
| What is relieved | Duty and import VAT on the suspended movement | Up to 99 percent of duties, taxes and fees originally paid, per our duty drawback guide |
| Ongoing obligation | Discharge the procedure and keep records (4 years standard in the UK) | Documented traceability between the import and the export claim |
Before you apply
- Work out which direction you actually need. Goods coming in for processing and going back out need IP. Goods already in the EU or UK going out for work and coming back need OP. They are not interchangeable.
- Check whether the goods are simply not changing at all. If nothing is being done to them, you likely want a temporary admission or carnet route instead, not a processing relief.
- Confirm your own establishment position in whichever customs territory you are applying in; both systems generally expect the applicant to be established there.
- Budget for the discharge and record-keeping obligation before assuming the duty saved is free money. A bill of discharge, or its EU equivalent, and years of retained records are the real cost of using either procedure properly.
- Get the valuation method right, particularly for OP, since duty is calculated on the value added abroad and not on the full re-import value; our guide to customs valuation covers how a dutiable value is built up in the first place, and getting that calculation wrong is a common source of later dispute.
- Consider whether a bonded warehouse solves the problem better. If the actual goal is deferring duty rather than processing the goods at all, a bonded warehouse or free trade zone may be the simpler tool.
Whichever side of a shipment you are on, having the right customs procedure in hand before goods move avoids a costly correction after the fact. If you need a forwarder who has actually handled a processing relief movement before, search more than 29,300 logistics companies by country and service in the CargoLinked directory, or post your shipment on the requests board and let forwarders who can quote come to you.
Authorisation conditions, thresholds and discharge periods for Inward and Outward Processing change and can vary by goods type and by customs authority. Confirm current requirements directly with HMRC, your member state's customs authority, or a customs broker before relying on any figure here.
