Fancy number banknotes are, simply said, banknotes with interesting serial numbers that set them apart from other ordinary banknotes of the same type. The attraction of fancy number banknotes is hard to explain, other than to say that it is almost primeval – an instinctive attraction to something out of the ordinary. Even non-collectors of banknotes will often set aside a currency note with a fancy number if they encounter one in day-to-day change.
More commonly encountered fancy numbers include “repeaters”, where the numbers repeat themselves, for example of 232323 or 168168; “radars” where the numbers read the same both forwards and backwards, for example 018810; and “low numbers”, for example 000028. “Hundred thousands” would be 100000, 200000 etc. The numbers in “ladders” go up, such as 123456; while “reverse ladders” just go in the opposite direction, or 654321.
The cream of the fancy numbers are the “solid numbers”, where all the numbers are the same, for example 888888; the “extremely low numbers”, usually referring to a single digit number, such as 000008; and the “one million”, literally 1000000. The “one million” used to be the last number of each prefix, and because of the extra digit, the numbers had to be manually printed. This number has since been discontinued, and the last number of each prefix is now the solid number 999999.
Even amongst the “solid numbers” and “extremely low numbers”, not all are created equal. There are “solid numbers”, and then there are “super solid numbers”. “Super solid numbers” are solid numbers where even the numbers in the prefix of the serial numbers are the same. An example is B/33 333333. While solid numbers are one in a million, super solids are literally one in a 100 million (or 2 in a 100 million if one counts single digit prefixes). And then there are “super-super solids”, where even the prefix letter is a representation of the same number, such as E/55 555555. These are practically unique in each series.
As for “extremely low numbers”, there are “extremely low numbers”, and there are extremely low numbers of the very first prefix. These are literally the very first serial numbers of each series. And then, there is the “number one”, which is self-explanatory. The king of it all, is the number one of the first prefix. Its twin brother would be the number one million of the last prefix, because for most issues (except for the $10,000), there is also a last prefix!
To top it all off, there are fancy numbers on replacement notes!
Nowadays, the Monetary Authority of Singapore (and its predecessor the Board of Commissioners of Currency, Singapore) sets aside some of the most popular of the fancy numbers from circulation and auction them to the public. This is much like the Land Transport Authority auctioning of car licence plate numbers, and we can all see how much some of them go for!
In the past, the first few numbers of the first prefix of each series were often reserved for officials. For the other fancy numbers, survival depend on luck and the eagle eyes of bank tellers and officers who pulled them out from circulation. This, coupled with the fact that the issue size of some earlier Singapore banknote denominations and signature varieties are very small, make some fancy number notes extremely rare and difficult to acquire. Many are literally one of a kind.