BMSB Season Is Back: What Importers Need to Know

If you import goods into Australia, 1 September is a date worth having on your calendar.

It marks the start of the 2026-27 Brown Marmorated Stink Bug (BMSB) risk season, bringing seasonal biosecurity measures back into effect for certain goods and vessels arriving from target risk countries.

BMSB might be a small insect, but it can create some very unwelcome problems for importers.

The bugs are known for hitchhiking on cargo, vehicles, machinery and vessels, particularly during the colder months in the Northern Hemisphere when they seek shelter in protected areas.

For Australia, the concern is what happens if they arrive here.

What does BMSB mean for your shipment?

The seasonal measures apply to targeted goods manufactured in or shipped from BMSB target risk countries where the goods are shipped between 1 September and 30 April inclusive.

For sea freight, the shipped-on-board date shown on the Ocean Bill of Lading is what determines whether the seasonal measures apply, not the date the goods are gated into the terminal.

Goods are divided into different categories.

Target high risk goods require mandatory BMSB treatment, while target risk goods may be subject to random onshore inspection. Other goods are not subject to the BMSB seasonal measures, although they can still be inspected if biosecurity concerns arise.

The list of target goods includes a range of products commonly associated with industrial and commercial imports, including certain machinery, vehicles and parts, as well as goods such as ceramics, stone products, rubber, plastics and textiles.

That is why it is important to check the classification of your goods before booking the shipment rather than discovering a treatment requirement once the cargo has arrived.

Offshore treatment can save headaches

For goods that require treatment, DAFF strongly encourages importers to arrange treatment offshore before the cargo arrives in Australia.

Treatment options include heat, methyl bromide and sulfuryl fluoride, with approved treatment providers required for offshore BMSB treatment. A new onshore treatment option, ethyl formate, has also been added for the 2026-27 season.

Getting the treatment and documentation right before the shipment arrives can help avoid unnecessary delays and additional costs.

And remember, BMSB requirements don't only apply to new goods. The same seasonal measures can apply to both new and used goods.

Don't leave it until the cargo is on the water

BMSB is one of those biosecurity requirements that is much easier to manage when considered at the beginning of the shipment. However, in some cases it is acceptable to have cargo treated on shore.

Before you book, check:

• Is the country of manufacture or shipment a BMSB target risk country?

• Is the cargo a target high risk or target risk commodity?

• Will it be shipped between 1 September and 30 April?

• Does it require treatment?

• Is the treatment provider approved?

• Is the required documentation in place?

A little planning before the shipment leaves can make a big difference when it arrives.

BMSB season runs from 1 September 2026 to 30 April 2027, so if you're importing from a target risk country over the coming months, now is the time to check the requirements.

If you're unsure whether your shipment is subject to BMSB measures, speak to your freight forwarder or customs broker before the goods leave.