The ASEAN+3 region expanded 4.3% in 2025, outperforming expectations despite what regional economists describe as the most significant shift in global trade policy in decades, according to the AMRO ASEAN+3 Regional Economic Outlook 2026.

A Region Built on Firm Foundations

The ASEAN+3 Macroeconomic Research Office (AMRO) — whose membership spans the ten ASEAN states plus China, Hong Kong, Japan, and Korea — attributes the region’s resilience to firm domestic demand, robust export performance, sustained investment, and deepening intraregional trade linkages. The region enters 2026 with most economies retaining meaningful fiscal and monetary policy space, a buffer regional policymakers built deliberately following the shocks of the preceding decade.

Two Risks Now Dominate the Outlook

AMRO identifies the balance of risks as tilted firmly to the downside for the year ahead, driven by two distinct but interacting shocks. First, the Middle East conflict and the resulting disruption to energy supply through the Strait of Hormuz pose what AMRO calls a significant near-term threat to both regional growth and inflation. Second, shifting US trade policy continues to inject two-sided risk into technology demand and broader trade flows, with financial market volatility compounding the downside pressure from both channels simultaneously.

Semiconductors Anchor the Region’s Trade Position

Regional semiconductor exports remain a structural strength even amid the broader uncertainty. AMRO’s data tracks ASEAN-6 semiconductor exports — spanning Indonesia, Malaysia, the Philippines, Singapore, Thailand, and Vietnam — as a critical driver of regional trade resilience, reflecting the bloc’s entrenchment in global chip and electronics supply chains at a moment when demand for AI-related hardware remains exceptionally strong globally, per AMRO’s full 2026 report.

China’s Property Drag Still Ripples Outward

Even as China’s export engine benefits from AI-driven demand, AMRO notes that overall Chinese investment remained slightly softer in the period under review, with spending on clean energy and advanced manufacturing only partly offsetting a prolonged property-sector adjustment. Given the depth of intraregional trade linkages AMRO’s own research documents, continued softness in Chinese domestic investment carries spillover implications for supply chains and demand across the wider ASEAN+3 bloc, even as China’s headline export growth remains robust.

The Regional Growth Picture, Country by Country

Within the bloc, growth trajectories are diverging. Indonesia, Singapore, and Vietnam are leading regional growth momentum into 2026, while Malaysia and Thailand continue to expand at a steadier, more moderate pace, and the Philippines lags due to domestic structural challenges, according to McKinsey’s Southeast Asia quarterly economic review. The Asia House Annual Outlook separately forecasts overall Asian growth easing to 3.8% from 4.1% according to WTO estimates, reflecting softer global demand, a modest China slowdown, and the fading effect of earlier supply-chain frontloading, though the region is still expected to outperform the global growth average, per Asia House’s 2026 outlook.

Preserving Policy Flexibility Is the Central Challenge

AMRO frames the region’s central policy challenge for 2026 not as responding to any single shock, but as preserving the flexibility to respond to whichever shock materializes first — whether a further escalation in Middle East energy disruption, a sharper-than-expected US tariff or technology-policy shift, or a deeper Chinese property-sector adjustment than currently modeled. For businesses and investors across Singapore, Malaysia, Indonesia, and the wider bloc, that framing suggests 2026 will reward economies and companies that maintain optionality rather than committing early to any single scenario for how the region’s twin external shocks ultimately resolve.

Indonesia, Southeast Asia’s largest economy, has committed to importing up to 150 million barrels of Russian crude oil through the end of 2026, a deal that goes well beyond emergency crisis management and increasingly resembles a deliberate, multi-year repositioning of the country’s energy security architecture away from a Middle East supply base that the Strait of Hormuz conflict has exposed as dangerously concentrated.

The agreement, finalized after President Prabowo Subianto‘s April visit to Moscow for direct talks with President Vladimir Putin, involves Russia supplying 100 million barrels of oil at a preferential price, with a further 50 million barrels available if Indonesia’s needs escalate, according to reporting from The Moscow Times. Hashim Djojohadikusumo, the president’s brother and a senior economic adviser, confirmed Indonesia has also secured Russian government commitment to store up to 150 million barrels domestically as a buffer against future volatility.

Why Indonesia Cannot Wait Out the Crisis

Indonesia’s exposure to Middle East supply disruption is structural rather than incidental. The country produces roughly 577,000 barrels of crude per day, according to May 2026 figures — well below the government’s 610,000 barrel target and a fraction of the roughly 1.5 million barrels per day the country produced in the 1990s, before mature field decline eroded domestic output, according to analysis published by OilPrice.com. Against consumption running near 1.6 million barrels per day, Indonesia faces a persistent daily supply deficit approaching one million barrels, forcing continuous reliance on imports for both crude and refined products.

Energy and Mineral Resources Minister Bahlil Lahadalia has been explicit about the scale of this dependence, noting Indonesia requires roughly 300 million barrels of imported crude annually while holding strategic reserves sufficient for only 21 to 23 days of consumption — a dangerously thin buffer for an economy of Indonesia’s size, according to reporting cited by OilPrice.com’s earlier coverage. Roughly 20-25% of Indonesia’s crude imports have historically transited the Strait of Hormuz, a route the ongoing conflict has rendered unreliable at precisely the moment global oil markets can least absorb additional supply shocks.

From Emergency Waiver to Structural Partnership

The diplomatic and commercial mechanics enabling this shift trace back to a US sanctions waiver for Russian crude issued on March 12, 2026 — a decision that, according to OilPrice.com’s analysis, effectively acknowledged that Asia could not balance its oil market without Russian barrels during a major Middle Eastern supply disruption. Successive extensions of that waiver have since encouraged regional buyers to treat Russian crude not merely as emergency supply, but as a legitimate, ongoing tool of energy security — a reframing with significant implications for how Asian governments approach sanctioned commodities going forward.

Indonesia’s pivot did not emerge in isolation. Rystad Energy analyst Prateek Panday characterized the country’s strategy as grounded in supply economics, refinery compatibility, and medium-term energy security logic rather than opportunistic crisis response, a framing echoed by analysts at Indonesia’s own Strategic and Economics Action Institution, who described the approach as a deliberate effort to reduce exposure to a single, highly escalation-sensitive supply cluster. Indonesia became a full BRICS member in January 2025 and subsequently signed a free-trade agreement with the Eurasian Economic Union, diplomatic groundwork that made the current energy partnership commercially and politically easier to execute than it would have been even eighteen months earlier.

Indonesia is far from alone in this recalibration. The Philippines began importing Russian crude under the same US waiver in March 2026, with state oil company Petron purchasing 2.5 million barrels in its first such deal since 2021 and receiving three cargoes across March and May. Vietnam has reportedly held its own talks with Moscow since March regarding a potential start to Russian oil imports — suggesting a broader regional realignment is underway across Southeast Asia rather than an isolated Indonesian policy choice.

Refinery Compatibility Remains the Critical Variable

Indonesia’s state oil company Pertamina has signaled openness to the deepening relationship while flagging a genuine technical constraint: compatibility between Russian crude grades and Pertamina’s existing refinery configuration. Pertamina spokesperson Fadjar Djoko Santoso (“Baron”) confirmed the company would conduct further studies on processing Russian crude, noting that refinery modernization efforts are expected to eventually give Pertamina’s facilities the flexibility to handle a broader range of crude types, according to reporting from the New Straits Times.

Early shipments offer a preview of the compatibility challenge. Only two vessels carrying Russian crude reached Indonesia in the six months preceding the Moscow summit, each transporting roughly 700,000 barrels of Sakhalin Blend — a light, sweet crude with an API gravity around 45 degrees and low sulfur content that makes it well suited to gasoline-oriented refining, according to OilPrice.com’s analysis. Scaling from two modest cargoes to a 150-million-barrel annual commitment will require substantially more logistics infrastructure, refinery testing, and shipping capacity than the current relationship has yet demonstrated.

Beyond Oil: A Broader Energy Alignment With Moscow

The Prabowo-Putin summit extended well beyond crude oil supply. Indonesia is separately exploring the development of floating nuclear power plants in partnership with Russian state nuclear company Rosatom, with CEO Alexey Likhachev describing commercial discussions following what he characterized as strong Indonesian interest in nuclear technology, according to reporting from Tempo. Indonesian Foreign Minister Sugiono has framed nuclear cooperation with Russia as part of a broader push toward energy self-sufficiency within three years, while stressing that any partnership must prioritize technology transfer and adherence to international safety standards.

Indonesia is also negotiating liquefied petroleum gas imports from Russia to address a widening domestic supply gap — LPG demand is projected to reach 10 million tons in 2026 against domestic production capacity of just 1.6 million tons, according to Minister Lahadalia, a gap previously filled predominantly by US and Middle Eastern suppliers whose reliability the current conflict has called into question.

What This Means for Global Energy Diplomacy

Indonesia’s pivot illustrates a broader pattern reshaping global energy trade in 2026: sanctions architecture designed around a binary compliant-versus-non-compliant framework is proving less durable when a major regional supply disruption forces large importing economies to weigh energy security against geopolitical alignment. What began as an exceptional, waiver-dependent response to the Middle East crisis is increasingly hardening into formal government-to-government infrastructure — storage agreements, refinery studies, and nuclear cooperation — that will likely persist well beyond whatever timeline the underlying Strait of Hormuz disruption eventually follows.

On a muggy Tuesday in March, Taro Yamamoto — operations director of a mid-sized Osaka precision-parts maker — stepped off a flight into Ho Chi Minh City for the third time in six months. He wasn’t scouting for components. He was scouting for customers. His domestic order book had contracted for the fourth consecutive year. His shop floor was greying, and two machine operators had retired with no replacements in sight. Back in Tokyo, the Tokyo Stock Exchange’s new capital-efficiency requirements had made inaction financially untenable. Across Japan, thousands of mid-sized executives are making exactly this calculation. The destination is almost always the same. The logic, once you see the numbers, is difficult to argue with.

The Arithmetic of Decline: Japan’s Domestic Squeeze

Japan has been living with a slow-motion structural crisis for the better part of three decades. The country’s population has fallen from its 2008 peak of 128 million and, by government projections, is set to slide toward 88 million by 2065. More than 29% of Japanese citizens are already aged 65 or older, making Japan the most demographically aged major economy on earth, as the IMF’s Finance & Development journal has documented. The working-age share of the population — those between 15 and 64 — has already fallen below 60%, the lowest among G7 nations. An aging society, as the IMF bluntly put it, “consumes less than a young one.”

For large multinationals — Toyota, Sony, SoftBank — the pivot overseas happened long ago. Their international revenue insulated them. It’s the mid-tier, the thousands of companies with 50 to 500 employees that form the backbone of Japanese manufacturing, services, and distribution, where the pressure is now acute. These firms were built to serve domestic demand. And domestic demand is structurally, irreversibly shrinking.

Set against this backdrop, Southeast Asia’s growth rates read like an alternate universe. The Asian Development Bank, in its December 2025 Outlook, revised the region’s GDP forecasts upward: growth of 4.5% for 2025, with Vietnam projected to expand by 6.6%, the Philippines at around 6%, and Indonesia at 5%. The IMF, speaking at the ASEAN Summit in October 2025, put it plainly: ASEAN is the world’s fourth-largest economy, with a collective GDP exceeding $4 trillion, growing 25% faster than the global average. For a Japanese mid-sized firm watching its addressable market contract at home, those numbers are not an abstraction. They are a survival map.

Why are Japanese companies expanding into Southeast Asia?

Japanese mid-sized companies are expanding into Southeast Asia because of converging structural pressures: a shrinking domestic consumer base driven by demographic decline, Tokyo Stock Exchange governance reforms compelling capital efficiency, the China-plus-one supply-chain imperative, and Southeast Asia’s sustained GDP growth of 4.5–6.6% across key markets — offering volume that Japan’s home market can no longer supply.

1 — The Core Development: A New Wave of Japanese Mid-Sized Companies Heading to Southeast Asia

The outbound push among Japanese mid-sized companies into Southeast Asia is not a new phenomenon. What’s changed is its scale, its urgency, and critically, the profile of the businesses involved.

For decades, it was Japan’s manufacturing giants — Hitachi, Panasonic, Bridgestone — that staked early positions across Vietnam, Thailand, and Indonesia. Their supply chains came first; their back-office operations followed. The mid-tier watched from the sidelines, constrained by capital, language barriers, and a domestic comfort zone propped up by decades of steady, if modest, home-market demand. That comfort zone has now dissolved.

JETRO’s FY2025 global survey of Japanese companies operating overseas — covering 7,485 valid responses across 82 countries — found that 66.5% of Japanese-affiliated overseas companies expect to be profitable in 2025, rising for the second consecutive year. The direction of expansion intentions tells a clearer story: survey respondents signalled growing appetite for Southwest Asia and ASEAN, while China — once the region’s default destination — continues to lose ground. In China, the proportion of companies anticipating business expansion hit an all-time low. The appetite is shifting, and it’s shifting south.

The structural driver is the “China plus one” strategy, which, by 2026, has stopped being a strategy and started being an operating assumption. Sino-American trade tensions, periodic supply-chain shocks, and rising Chinese labour costs have pushed Japanese manufacturers to seek parallel production bases. Vietnam has emerged as the primary beneficiary, attracting Japanese automakers, electronics suppliers, and — increasingly — second-tier parts makers who once fed larger Japanese manufacturers. Thailand, with its mature automotive industrial base and 60-year-old Japanese manufacturing presence, continues to draw mid-sized component makers. Indonesia, with its population of 280 million and a PMI that hit a multi-month high of 53.6 in early 2025 according to S&P Global data, is drawing fresh interest from consumer-goods manufacturers seeking volume markets.

UNCTAD’s 2025 FDI Explorer data shows ASEAN inflows hit a record $225 billion in 2024, up 10%, even as Europe’s FDI collapsed and China’s fell 29%. The region absorbed capital when almost nowhere else did.

What’s different now is who is moving. It’s no longer primarily the large enterprise with a dedicated global-expansion team and a Singapore holding company. It’s the Osaka die-caster, the Nagoya food-equipment manufacturer, the Fukuoka logistics-software firm — businesses that, until recently, had neither the appetite nor the architecture for foreign operations.

2 — The Structural Logic: Why Southeast Asia, Why Now?

The question most analysts ask is why the timing. The answer is a convergence of four pressures that have, in 2025 and 2026, reached simultaneous critical mass.

What is driving Japanese mid-sized companies to expand into Southeast Asia?

Japanese mid-sized companies are expanding into Southeast Asia because of converging structural pressures: a shrinking domestic consumer base driven by demographic decline, Tokyo Stock Exchange governance reforms compelling capital efficiency, the China-plus-one supply-chain imperative, and Southeast Asia’s sustained GDP growth of 4.5–6.6% across key markets — offering volume that Japan’s home market can no longer supply.

First, the demographic arithmetic, already described, is irreversible on any business-relevant time horizon. Companies can adapt temporarily — through automation, productivity gains, pricing — but they cannot manufacture new Japanese consumers. The medium-term demand trajectory at home is fixed. Growth, if it comes, must come from somewhere else.

Second, the TSE’s corporate governance overhaul — which since 2023 has placed intense scrutiny on companies trading below book value — has created a new accountability mechanism. Japanese mid-sized firms, traditionally patient with low returns, are now under pressure from institutional investors to demonstrate capital efficiency. Overseas expansion, with its attendant revenue diversification, has become a credible answer to that pressure. As documented by analysts writing for Insignia Business Review, the TSE’s push on price-to-book ratios is “forcing Japanese companies to think differently about partnerships, including those with international firms.”

Third, U.S. tariff policy has injected a new and urgent variable. Japanese manufacturers heavily embedded in Chinese supply chains face cost exposure that’s now structural, not cyclical. The premium on supply-chain geographic diversification has risen sharply since the Trump administration’s tariff expansions, and ASEAN — with its favourable trade agreements, including RCEP and CPTPP — offers a route around the worst of the exposure.

Fourth, and perhaps least discussed, is the sheer scale of Southeast Asia’s consumer base. The region’s middle class is expanding at a rate that has no parallel in Japan’s recent history. J.P. Morgan research has projected the internet economy across six key ASEAN markets approaching $360 billion in gross merchandising value. For a mid-sized Japanese food manufacturer, a health-care-products company, or a retail-concept operator, that is not a distant opportunity. It’s a currently accessible, rapidly deepening market — and Japanese brands, given the cultural cachet they carry across the region, start with a significant standing advantage.

3 — Implications and Second-Order Effects

The shift carries consequences that extend well beyond the balance sheets of individual companies.

For Japan itself, the most immediate concern is what economists sometimes call the “hollowing out” risk. When large Japanese manufacturers moved production offshore in the 1990s, domestic suppliers suffered. If the current wave of mid-sized firms follows not just with production but with their management, R&D, and commercial operations, the domestic economic base could erode further. Japan’s Ministry of Economy, Trade and Industry has acknowledged this tension in its 2025 White Paper on International Economy and Trade, which frames overseas expansion as necessary for value creation while simultaneously signalling concern about domestic industrial capacity.

For Southeast Asian host economies, the implications are broadly positive but uneven. Vietnam and Thailand, which have the most established Japanese industrial infrastructure, are best positioned to absorb further waves of investment quickly. Indonesia faces more complex challenges: its logistics infrastructure, while improving, still lags Vietnam’s in efficiency for export-oriented manufacturing. Malaysia, meanwhile, is seeing a particular surge — S&P Global’s 2025 Reshoring Special Report found that 28% of Malaysian manufacturers reported increased demand tied to reshoring, up sharply from 20% in 2024, with medium-sized firms particularly optimistic.

For the broader regional trade architecture, the Japanese mid-sized firm’s arrival accelerates something that was already underway: the transformation of ASEAN from a primarily large-enterprise investment zone to a genuine habitat for mid-market global capital. That shift has compounding effects. Japanese SMEs bring with them supplier relationships, technology transfer, and operational know-how that seed local industrial ecosystems. In Vietnam’s industrial provinces, the downstream effect of Japanese mid-tier manufacturers has been the emergence of local sub-suppliers and component fabricators that did not exist a decade ago.

There’s a currency dimension, too, that shouldn’t be underplayed. The yen’s extended period of weakness — a consequence of the Bank of Japan’s historically accommodative stance and the slow pace of normalisation — has paradoxically made overseas investment cheaper in yen terms, even as it erodes repatriated profits. Companies with significant local-currency revenue in baht, dong, or rupiah are, in effect, hedging against further yen weakness. The financial calculus has shifted in ways that favour commitment over caution.

4 — The Counterarguments: Not Every Mid-Sized Firm Should Go

The enthusiasm carries real risks, and anyone advising Japanese mid-sized firms on Southeast Asian expansion would be negligent to paper over them.

The first is operational. Large corporations move to ASEAN with teams of experts, legal counsel, and institutional knowledge accumulated over decades. Mid-sized firms typically don’t. The complexities of establishing a subsidiary in, say, Indonesia — navigating local-ownership rules, labour regulations, tax treaties, and sometimes opaque licensing processes — can overwhelm companies that lack dedicated international capacity. Research published in the journal Asia Pacific Business Review documented that some Japanese firms that expanded into Thailand and Indonesia in the mid-2010s subsequently withdrew, citing rising labour costs, talent shortages, and intensifying competition from Western companies. Those conditions have not uniformly improved.

The second risk is the competitive environment itself. Japanese mid-sized firms arriving in Vietnam or Indonesia in 2026 are not entering empty markets. Chinese manufacturers — displaced by tariffs or simply pursuing their own internationalisation — are competing aggressively for the same factory sites, the same skilled workers, and the same distribution channels. The JETRO survey noted that concerns about “intensifying competition with Chinese companies” ranked among the top worries for Japanese manufacturers in Asia.

Third, the World Bank’s April 2026 East Asia and Pacific update flagged that Southeast Asian growth itself faces a slower trajectory — projecting a regional moderation to 4.2% in 2026, down from 5%, partly because of the conflict in the Middle East and its effect on energy prices. Thailand, in particular, is struggling, with forecast growth of just 1.3% in 2026, dragged by high household debt and political uncertainty. A company that entered Thailand’s market betting on strong consumer growth may find the reality more complicated than the prospectus suggested.

The picture is more complicated still for firms without a clear competitive differentiation. Japanese brand cachet travels far in Southeast Asia, but it is not infinite. It doesn’t automatically compensate for a product that’s 30% more expensive than a local equivalent, or a distribution model that was built for Japanese retail formats and doesn’t translate.

Closing: The Point of No Return

There is something close to inevitability in what is happening. Japan’s mid-sized companies are not choosing to internationalise so much as accepting that the alternative — remaining anchored to a structurally contracting domestic base — is its own form of decline. The question isn’t whether to move, but whether to move with enough preparation and self-awareness to avoid the mistakes of those who moved before.

Southeast Asia will absorb this capital. The region has the demographic momentum, the infrastructure investment trajectory, and the trade architecture to sustain Japanese mid-tier ambitions for at least the next decade. What the region cannot guarantee is that every company that arrives will thrive. The mid-sized firms that succeed will be those that treat the region as a set of distinct, demanding markets — not as a single, grateful alternative to the one they left behind.

Japan’s corporate middle is heading south. The question that will define the next chapter is not whether, but how well.