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Customs duty, GST and biosecurity on an imported prefab home
| Customs duty, heading 9406 | 5% general rate[1] |
|---|---|
| Free trade agreement goods | Free if the goods qualify as originating[1][2] |
| GST | 10% of the value of the taxable importation[3] |
| Import declaration | Duties, taxes and charges apply above A$1,000[4] |
| Biosecurity season | Brown marmorated stink bug measures for goods shipped 1 September – 30 April[5] |
| Asbestos | Prohibited import[6] |
A prefabricated building imported into Australia attracts customs duty at a general rate of 5%, falling to free where the goods qualify as originating under a free trade agreement such as the one with China.[1][2] GST of 10% is then charged on the customs value plus duty, transport and insurance.[3] Shipments between 1 September and 30 April can be caught by stink bug biosecurity measures, and any asbestos content makes the goods a prohibited import.[5][6]
This guide covers what happens when an imported home crosses the border, before any question of building approval arises. Clearing these steps is the importer's job, done directly or through a licensed customs broker.[4]
Customs duty §
Imported goods are classified under the Customs Tariff, and the classification sets the duty rate. Prefabricated buildings fall under heading 9406, at a general rate of 5% for buildings of wood, steel modular units and other prefabricated buildings alike.[1]
Lower rates apply depending on where the goods come from. The tariff shows a free rate for goods from Canada, and free rates for New Zealand, Papua New Guinea, Forum Island countries, developing and least developed countries and Singapore unless otherwise indicated.[1] It also states that goods originating under a free trade agreement are free unless the relevant schedule says otherwise.[1]
Free trade agreement rates
The free rate is not automatic. Under the China–Australia agreement, for example, the goods must meet the agreement's rules of origin; goods that do not meet them pay the general rate.[2] The importer generally needs a certificate of origin issued by an authorised body in China, and must keep records for five years.[2] If the preference is not claimed at the time of import, a refund can be sought later — within 12 months where the certificate is issued afterwards, or within four years if a certificate was already held.[2]
Anti-dumping measures
Some imported goods carry extra duties because the Anti-Dumping Commission has found them to be dumped or subsidised. The Commission keeps a public register of goods subject to these measures, by tariff classification and country.[7] Whether any measure applies to a particular shipment is not covered by the sources compiled here.
GST on imports §
GST of 10% applies to the value of the taxable importation. That value is the customs value plus customs duty, the cost of transporting the goods to their destination in Australia and the insurance on that transport.[3] GST is collected by the Department of Home Affairs and is generally paid before the goods are released.[3]
Registered businesses importing for a creditable purpose can claim the GST back as a credit, and eligible registered importers can defer payment to their activity statement.[3]
How GST applies to the later sale or installation of a home in Australia is a separate question, covered in GST on tiny homes, modules and transportable buildings.
The import declaration §
Goods are cleared through an import declaration, lodged by the importer or by a licensed customs broker on their behalf. For most goods valued over A$1,000, all duties, taxes and charges apply, including an import processing charge.[4] Border Force encourages first-time and occasional importers to use a licensed customs broker.[4] A prefab home is well above that threshold.
Biosecurity §
Biosecurity conditions are set by the Department of Agriculture, Fisheries and Forestry and published in its import conditions system, BICON. Conditions vary by commodity.[8]
The rule most likely to affect a prefab shipment is the seasonal measure for the brown marmorated stink bug. It applies to targeted goods made in or shipped from target risk countries between 1 September and 30 April, judged by the shipped-on-board date.[5]
| Goods | From | What applies | Source |
|---|---|---|---|
| Wood, steel, aluminium, glass, ceramics and cement articles (tariff chapters 44, 68–70, 72, 73, 76) | Target risk countries, including the United States, Canada, Germany and most of continental Europe | Mandatory treatment | DAFF[5] |
| Prefabricated buildings and furniture (chapter 94), plastics (39) | Emerging risk countries: United Kingdom, China, Japan, Republic of Korea | Random onshore inspection | DAFF[5] |
Untreated break bulk cargo in the high-risk categories is directed for export.[5] Which group a shipment falls into depends on how its goods are classified and where they come from: goods classified under chapter 94 and shipped from China are in the random inspection group, while goods classified under the wood, steel or glass chapters and shipped from a target risk country need mandatory treatment.[5] The measures apply only to goods shipped within the seasonal window.[5]
Prohibited goods §
Asbestos is a prohibited import, and a supplier's asbestos-free declaration is not accepted as evidence on its own.[6] Border Force recorded a prefabricated building among its asbestos detections in 2025–26 — see Border Force finds asbestos in an imported prefabricated building for what it accepts as proof.
What is not covered here §
Not covered by the sources compiled here: how a particular building or set of components is classified; the import processing charge amounts; rules of origin under agreements other than the one with China; whether any anti-dumping measure applies to a particular product; biosecurity conditions other than the stink bug season, including timber treatment and packaging rules; port, freight and storage charges; and state stamp duty, which is covered in stamp duty on a modular, transportable or kit home. Clearing customs says nothing about whether the home can be approved and lived in; that is covered in imported prefab kits — what compliance requires.
Related guides:
- Importing a prefab home into Australia
- What Australia imports in prefabricated buildings
- Buying an imported prefab home from an overseas supplier
- Delivery, transport and craneage
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References §
- Australian Border Force — Customs Tariff, Schedule 3, Chapter 94, operative 1 July 2026. Heading 9406 prefabricated buildings — 9406.10.00 of wood, 9406.20.00 modular building units of steel, 9406.90.00 other — each at a general rate of 5%, with a free rate shown for Canada (CA). Footnotes state that unless otherwise indicated the NZ, PG, FI, DC, LDC and SG rates are free, and that unless indicated in the relevant schedule, rates for originating goods under a free trade agreement are free. abf.gov.au/importing-exporting-and-manufacturing/tariff-classification/current-tariff/schedule-3/section-xx/chapter-94
- Department of Foreign Affairs and Trade — Guide to using ChAFTA to export or import. Goods must meet the agreement's rules of origin to receive the preferential rate, otherwise the general rate applies; importers generally need a certificate of origin from an authorised body (in China, the General Administration of Customs or the China Council for the Promotion of International Trade) or, in limited cases, a declaration of origin; none is required where the total customs value is under A$1,000; importers must keep records for five years; where a preference was not claimed at import, refunds can be sought within 12 months for a retrospectively issued certificate, or four years if a certificate was held at the time of import. dfat.gov.au/trade/agreements/in-force/chafta/doing-business-with-china/guide-to-using-chafta-to-export-or-import
- Australian Taxation Office — GST and imported goods, last updated 13 May 2024. GST on taxable importations is 10% of the value of the taxable importation, which is the customs value plus customs duty, the cost of transport to the destination in Australia, insurance for that transport and any wine tax. GST is collected by the Department of Home Affairs and is generally paid before the goods are released; eligible GST-registered importers can defer it; registered businesses importing for a creditable purpose can claim a GST credit. ato.gov.au/businesses-and-organisations/gst-excise-and-indirect-taxes/gst/in-detail/rules-for-specific-transactions/international-transactions/gst-and-imported-goods/
- Australian Border Force — Import declaration. Declarations are used by importers, or licensed customs brokers on their behalf, to clear goods. All imported goods are liable for duties and taxes unless an exemption or concession applies; for most goods valued at A$1,000 or less there are no duties, taxes or charges; above A$1,000 all relevant duties, taxes and charges apply, including an import processing charge. First-time or infrequent importers are encouraged to use a licensed customs broker. abf.gov.au/importing-exporting-and-manufacturing/importing/how-to-import/import-declaration
- Department of Agriculture, Fisheries and Forestry — Seasonal measures for brown marmorated stink bug (BMSB), with updates dated 5 August 2026. Measures apply to targeted goods made in or shipped from target risk countries between 1 September and 30 April inclusive, using the shipped-on-board date. Target risk countries include the United States, Canada and most of continental Europe, among them Germany. Target high risk goods requiring mandatory treatment include tariff chapters 44 (wood), 68 (stone, plaster and cement articles), 69 (ceramics), 70 (glass), 72 and 73 (iron and steel) and 76 (aluminium). Goods in chapters 39, 94 and 95 are subject to random inspection when shipped from the emerging risk countries — the United Kingdom, China, Japan and the Republic of Korea. Untreated break bulk target high risk goods are directed for export. agriculture.gov.au/biosecurity-trade/import/before/brown-marmorated-stink-bugs
- Australian Border Force — Asbestos, page last updated 23 September 2026. Importing asbestos or goods containing it is prohibited unless a permission is granted or an exception applies; an asbestos-free declaration is not evidence on its own. abf.gov.au/importing-exporting-and-manufacturing/prohibited-goods/asbestos
- Anti-Dumping Commission — Current measures, dumping commodity register. The register lists imported goods subject to anti-dumping or countervailing measures, by tariff classification and country of export; measures can change as cases progress. industry.gov.au/anti-dumping-commission/current-measures-dumping-commodity-register-dcr
- Department of Agriculture, Fisheries and Forestry — Review of import conditions. BICON, the Biosecurity Import Conditions system, is where the department publishes import conditions; conditions vary by commodity, and importers can subscribe to notices or follow a commodity to be told of changes. agriculture.gov.au/biosecurity-trade/import/online-services/bicon/review-import-conditions
Figures are as published by the sources above at their respective dates and are paraphrased summaries, not verbatim reproductions. Verify current pricing and rules directly with builders, lenders and planning authorities.