Torn banknote: does half a bill get you half its value?

The Bank of Korea looks at notes that still have both their front and back, and checks what fraction of the original size remains. A note with a slightly torn corner is above three-quarters, so it gets full value. A note with about half left is above two-fifths but below three-quarters, so it gets half, and a scrap of about one-third cannot be exchanged.

You can tape several pieces together and bring them in. Only pieces from the same note are added together, though. If water or fire has made the paper shrink or stretch, the note is measured at its changed size.

The interesting part is that the half-value line is two-fifths, not one-half. Thanks to that number, tearing one note on purpose can never get you more than its face value. A single note can have at most two pieces larger than two-fifths, so even if both get half value, together they add up to exactly one note. If one piece is above three-quarters and gets full value, the rest is less than a quarter and gets nothing.

Many people think "half a note, half the money," but a piece smaller than half still gets half value as long as it is over two-fifths. On the other hand, even a piece well over half gets only half value if it falls short of three-quarters.

Burned notes are exchanged under the same rules, and the ash matters. If the ash has not scattered and still holds the shape of the note, the ash counts as part of the remaining area. So don't panic and brush it off or tidy it up; carry it in as it is in a box, bowl or dustpan. If the money burned inside a wallet or small safe, bring it in that container.

Coins are treated more generously. Even if they are bent or rusty, they are exchanged at full value as long as you can tell what they are. There is no fee, and if the damage is easy to judge, nearby banks, including Nonghyup, Suhyup and the post office, can exchange it too. Heavily burned money that is hard to judge must go to the Bank of Korea's head office or a regional branch.