Tariffs Stack, Hormuz Bites: ASEAN Operators Face a Costlier, Slower Fourth Quarter

US tariffs stack on ASEAN exporters

The 90-day US reciprocal tariff pause expired in July 2026 without completed bilateral deals for most ASEAN markets, restoring elevated duties of 10-49 percent on goods from Vietnam, Indonesia, Thailand and Cambodia (per USTR Federal Register notice, 18 August 2026). Layered on top, the Section 122 global tariff surcharge of 10 percent takes full effect for all companies from 29 September 2026, replacing the prior IEEPA regime across nearly all US trading partners (per Zonos US Import Tariff Tracker, 11 September 2026).

For operators with US-bound manufacturing or sourcing in ASEAN, this is a stacking event: reciprocal duties plus a universal surcharge plus, for seven ASEAN economies, existing Section 301 forced-labor tariffs of 10-12.5 percent from July (per Industrial Automation Asia, 4 August 2026). Decision: recompute landed cost models now against the full stack, not each measure in isolation, and prioritize renegotiation of US customer contracts before Q4 shipments lock in.

10% Section 122 global surcharge, effective 29 Sept 2026

Indonesia's SOE export mandate goes live

Government Regulation 24/2026 now restricts exports of coal, palm oil and ferroalloys to a single designated SOE entity (DSI), displacing existing foreign-held export-facing roles (per HLC Publications, 29 August 2026). The mandate, first flagged to parliament in May 2026, was targeted for September 2026 implementation and directly threatens long-term supply contracts with Japan and Korea (per Indonesia's Export Control Plan report, 24 July 2026).

Foreign companies with direct export contracts in these commodities must restructure around DSI as owner or sole intermediary. Decision: audit all coal, palm oil and ferroalloy export contracts this month for DSI pass-through clauses, and open parallel conversations with Japanese and Korean offtakers who face the same contract risk, since coordinated renegotiation carries more weight than bilateral asks.

Steel transshipment through ASEAN draws scrutiny

China exported over 131 million metric tonnes of steel in 2025, up 13.8 percent from 115 MMT in 2024, with ASEAN absorbing a disproportionate share of the surplus (per OECD Steel Outlook 2026, 28 August 2026). In 88 documented product-country cases where OECD members imposed anti-dumping or countervailing duties on China, ASEAN-origin exports of the same products to OECD markets rose afterward, alongside a 300 percent surge in China's semi-finished steel shipments to Southeast Asia (per OECD Steel Outlook 2026, 3 August 2026).

This pattern points to ASEAN increasingly functioning as a transshipment corridor, which raises the risk of OECD members extending trade remedies to ASEAN-origin steel. Decision: manufacturers sourcing ASEAN steel inputs should document supply-chain origin now, ahead of any extension of AD/CVD measures to the region.

131 MMT China 2025 steel exports, up 13.8% YoY

Hormuz disruption keeps energy costs elevated

Iran's closure of the Strait of Hormuz since 4 March 2026 has locked out roughly 20 million barrels a day of global oil flow, with at least 17 merchant ships damaged and a US-led naval escort and aerial campaign ongoing (per Congress.gov, 31 August 2026). Even after a June 2026 US-Iran interim deal moderated Brent from around 120 dollars a barrel, Iran continues to assert transit fees and vessel control rights, and a Saudi supertanker and Qatari LNG carrier have since been attacked (per Oxford Energy Forum, 29 July 2026).

The supply shock is visible in producer results: Saudi Aramco's Q2 2026 hydrocarbon output fell to 9.5 million barrels of oil equivalent per day, down from 12.614 mmboed in Q1 2026 and 12.780 mmboed a year earlier, with crude averaging 108 dollars a barrel (per Energies Media, 19 August 2026). Decision: energy-intensive ASEAN manufacturers and shippers should stress-test 2026 budgets against sustained elevated crude pricing rather than assume a quick return to pre-crisis levels.

9.5 mmboed Aramco Q2 2026 output, down from 12.78 mmboed a year earlier

Freight costs spike into China's National Day holiday

Shanghai-Los Angeles container rates climbed to 7,185 dollars per FEU as carriers including Cosco pulled roughly 20 percent of capacity through blank sailings ahead of China's National Day holiday demand surge (per J.M. Rodgers Co., 24 September 2026). Separately, EU member states must begin collecting a new per-parcel handling fee on distance-sale consignments no later than 1 November 2026, adding cost to cross-border e-commerce shipments into Europe (per Consilium press release, 9 September 2026).

Decision: shippers with October US or EU-bound cargo should confirm booking positions now given reduced capacity, and e-commerce operators selling into the EU should price the incoming parcel fee into Q4 landed-cost quotes ahead of the Commission's delegated act setting the fee level.

$7,185/FEU Shanghai-LA container rate, 24 Sept 2026

Rate policy diverges as Fed holds and BOJ hikes

The Federal Reserve's September 16 meeting followed a divided 9-3 July vote to hold at 3.50-3.75 percent, with CME FedWatch showing a 58.6 percent probability of a hold after Fed Chair Kevin Warsh's hawkish Jackson Hole remarks lifted the dollar index (per CME FedWatch, 3 September 2026). Meanwhile the Bank of Japan raised its policy rate to 1.0 percent in late July 2026, the first move to this level in over 30 years, with officials signaling further hikes are likely (per Trading Economics, 29 July 2026).

The widening US-Asia rate differential is pressuring ASEAN currencies, including the rupiah. Decision: treasury teams should revisit FX hedging on USD-denominated payables and JPY-linked financing given the direction of both central banks this quarter.

1.0% BOJ policy rate after July 2026 hike