Seven Centuries of Trade, Trust, and Transformation

It is such an honor to be asked to write about Japan and Thailand’s long history of economic success. I have lived over half my life in Asia, and those 40+ years were spent in both Japan and Thailand. Two countries that are very dear to me. Two countries that have been developing sound economic relations for hundreds of years.

Prior to 1939, Thailand was known as Siam, and Siam and Japan had been doing business for approximately 600 years, with regulated and structured economic relations dating back about 140 years.

Early commercial and diplomatic contacts between Japan and Siam’s Ayutthaya Kingdom began in the 15th century.

Japanese “red seal ships” regularly traded with Siam back in the early 1600s, when trade primarily involved Japanese silver and handicrafts traded for Thai sappanwood and deerskins.

The sizable Japanese Nihonmachi community, acting as a central hub for trade, was established and actively trading during that same period.

Formal diplomatic relations began with the Declaration of Amity and Commerce between Japan and Siam, signed on 26 September 1887.

Since then, Japan has become a key economic partner for Thailand.

Designed to eliminate tariffs on more than 90% of bilateral trade within 10 years, the Japan–Thailand Economic Partnership Agreement (JTEPA) was a major milestone in 2007.

Thailand exports a wide range of manufactured and agricultural food products to Japan, while Japan remains one of Thailand’s largest and longest-standing investors, particularly in automobiles, machinery, and electronics.

Japan views Thailand as an ideal gateway to the 600‑million‑plus ASEAN market due to its central location and logistics links.

Thailand’s BOI reported that Japanese investment applications in the industrial sector rose 146% in 2025 to about 119 billion baht, compared to 2024.

Thailand’s 2026 started off well, with overall foreign investment rising about 46% year‑on‑year, with Japan among the top three investing countries, alongside Singapore and China.

Over the years, we have witnessed the evolution of ‘Wellness and Quality of Life’ as an integral part of the Thai cultural landscape, with Thailand ranking third in the world for Wellness Tourism.

No longer a marketing tool for Thailand’s residential and hospitality sectors, healthy living has developed into a long-term core initiative for the Thai wellness industry.

Japanese visitors report a strong interest in Thai wellness services and herbal products and indicate that their expectations for quality and privacy are met to a high degree.

Wellness tourism has grown to include holistic and medical retreats, with hotels offering features such as evidence-based therapies (EBTs), personalized nutrition, meditation and more.

With their ageing population, Japanese consumers recognize the Thai wellness industry as an excellent, affordable, and convenient alternative to their expensive elder care back home in Japan.

Thailand is quickly establishing itself as a global financial and digital hub. The foundation of this shift is the recent 2025 ‘Financial Business Hub Act’ and related reforms. Together, these improvements offer a more flexible regulatory environment and a focus on reducing operating costs.

Thailand’s Eastern Economic Corridor (EEC) is a special economic zone located on Thailand’s Eastern Seaboard. The EEC was created to transform the region into a leading ASEAN hub. Based on total investment value and the number of investors, Japan is currently the EEC’s largest foreign investor, and recent initiatives have attracted a new wave of commitments from Japanese automakers.

The year 2026 represents a defining moment for the Japan–Thailand partnership. It serves as a bridge between the 2022–2026 strategic plan and the next cycle beginning in 2027. As the current Five‑Year Joint Action Plan draws to a close, both sides are taking stock—evaluating achievements, identifying gaps, and deciding where to raise the bar. This is also the period when government agencies and leading institutions will work together to shape the new roadmap, timed to coincide with the 140th anniversary of diplomatic relations between Japan and Thailand. The focus now extends beyond traditional trade and manufacturing ties toward green innovation, digital transformation, wellness, and co‑creation.

As Japan and Thailand progress through 2026, they look to renew their partnership as it evolves beyond the established roles of their past. Together, they will focus on essential aspects of cooperation such as the green economy, wellness tourism, and digital innovation. They will target their efforts on the 2027 review of the Japan–Thailand Economic Partnership Agreement (JTEPA), which will open new avenues for discussion on regional growth and emerging industries.

In many ways, 2026 will act as the testing ground for how both nations will mobilize investment, co-develop solutions, and extend their shared influence across the Asia Pacific in the years ahead.

Yes, Over Seven Centuries of Trade, Trust, and Transformation: A Lasting Alliance between Japan and Thailand.

About the Author: Clayton Wade

Clayton Wade has spent more than four decades living in Asia. With his life divided between Japan and Thailand, he brings an understanding of these two economies that goes beyond research, shaped by the cultural rhythms, business philosophies, and overlooked shifts that only long residency reveals. From the trade expansions of the late 20th century to the pressures of today’s digital age, he’s watched the region’s transformation not from a distance, but from within it.

As both observer and participant in the ASEAN market’s shifting landscape, Clayton writes with authority on how the Japan–Thailand partnership is moving toward green innovation, wellness tourism, and digital co-creation. His work is anchored in a deep respect for the 600-year commercial history between these nations, and aimed squarely at what’s to come.