A Collector’s Guide to Japanese Invasion Money (JIM)

During World War II, as Imperial Japan rapidly expanded across the Pacific and Southeast Asia, it replaced local currencies with its own form of military-issued money known as Japanese Invasion Money (JIM). These notes, now collectible relics of wartime history, were printed in large quantities for use in occupied territories, and they tell a fascinating story of wartime economy, control, and propaganda.

Whether you’re a seasoned collector or just discovering these historical notes, here’s everything you need to know about JIM—including where it was issued, how to decode the markings, and which ones are rare.

What Is Japanese Invasion Money?

JIM was fiat currency printed by Japan to be used in occupied territories during WWII. Because Japan’s forces didn’t want to use or legitimize Allied currencies, they created localized notes for the regions they controlled. While JIM was initially accepted, its value quickly deteriorated due to overprinting and the collapse of Japanese infrastructure, leading to hyperinflation and resentment from local populations.

Countries Where JIM Was Issued

Japanese Invasion Money was issued across multiple occupied regions, tailored to each country’s language and monetary system. Here’s a breakdown:

1. Philippines

2. Burma (Myanmar)

3. Malaya (Malaysia & Singapore)

4. Netherlands East Indies (Indonesia)

5. Oceania (e.g., Papua New Guinea, Solomon Islands)

6. Hong Kong

Understanding the Markings: Serial Numbers, Prefixes, and Bracketed Numbers

JIM notes were printed with a variety of markings that help identify their origin, denomination, and sometimes even the printing batch. Here’s what to look for:

1. No Serial Numbers

Low-denomination notes (like 1 or 10 centavos/gulden) were often printed without serial numbers to speed up production and reduce printing complexity. These were considered less prone to counterfeiting due to their low value.

2. Serial Numbers

Higher-denomination notes almost always have serial numbers. These were important for tracking and anti-counterfeiting, especially as forgeries became more common.

3. Bracketed Numbers (e.g., {4})

These indicate the position of the note on the printing sheet or the plate number. They’re not directly tied to the note’s value but help collectors and researchers trace the printing process.

4. Prefix Codes (e.g., MA, PH, OB)

The two-letter codes at the start of serial numbers (sometimes boxed) indicate the region of issue, printing batch, or denomination type. Some prefixes are more common than others—and that’s where the rarity factor comes in.

Rare Prefixes to Watch For

While most JIM notes are common and valued modestly ($1–10), some prefix codes are significantly rarer and can increase a note’s value—especially in uncirculated condition.

Malaya & Borneo (Prefix “M”)

Philippines (Prefix “P”)

Burma (Prefix “B”)

Netherlands East Indies (Prefix “S”)

Oceania (Prefix “O”)

Japanese Invasion Money serves as a vivid historical artifact from one of the most turbulent periods of the 20th century. Whether you’re drawn by its design, its history, or its collectible potential, these notes offer a tangible connection to WWII’s global impact. Pay attention to serials, prefix codes, and condition—because what may look like just a piece of old paper might be a rare survivor of wartime economics.