The band edges and privileges you’ve memorized for US amateur radio aren’t universal. The International Telecommunication Union divides the world into three regions, and band plans, and sometimes even which frequencies are allocated to amateurs at all, genuinely differ between them.
The three ITU regions
ITU Region 1 covers Europe, Africa, the Middle East, and most of the former Soviet Union. Region 2 covers North and South America, including the US, along with Greenland. Region 3 covers most of Asia and Oceania. Each region negotiates its own spectrum allocations at World Radiocommunication Conferences, which is why an amateur band that exists cleanly in one region might be split differently, or not exist at all, in another.
Where the differences actually show up
The clearest example is 60 meters, where allocations, power limits, and even whether the band exists at all vary noticeably between regions. 40 meters is another good example: Region 1 hams have a narrower 40 meter allocation than Region 2, since part of that spectrum is shared with broadcast stations in Region 1 but not in the Americas. Even where a band exists in all three regions, subband boundaries for different modes don’t always line up exactly.
Why this matters for your own operating
When you’re working DX, remember that the station on the other end may be operating under genuinely different band edges and mode restrictions than you are, which is part of why some contacts happen slightly outside where you’d expect activity on your own region’s band plan. If you ever operate from another country, whether visiting or through reciprocal licensing arrangements, checking that region’s specific band plan before transmitting is essential, not optional, since assuming your home band plan applies everywhere is an easy way to accidentally transmit somewhere you shouldn’t.
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