There are three instances I know of where two flags are color-swapped. By that, I mean that the flags are the same except where flag A has color M, flag B has color N, and where flag A has color N, flag B has color M. There’s actually more than three, but I’m excluding bicolors and tricolors.
One of the three is deliberate, one may be deliberate, and the other is mostly accidental. Some people may want to treat this as a trivia question, so I’m going to hide what they are.
Cuba and Puerto Rico – definitely deliberate, both adopted in the 19th century before Cuba was independent. Puerto Rican nationalists deliberately copied the flag of Cuban nationalists.
Switzerland and the International Red Cross – this may be deliberate. I remember reading that someone at the organizing meeting proposed color inverting the Swiss flag to make a symbol for the new organization, but Wikipedia says there’s no evidence for it. Related is the Red Crescent flag which is a switched version of the Turkish flag, but since the star on the Turkish flag is left out, I’m not counting it.
Norway and Iceland – this one appears to be accidental, well except that both have the Scandinavian cross. Also the shades of blue are not exact, but they’re close enough that I’m counting it.
So are there any others? They don’t have to be national flags, any official or even just commonly used flags are acceptable. But remember, I’m not interested in bicolors or tricolors, so Indonesia and Poland, for example, don’t count.
Impressive list, mbh. You really did your homework there. But the Sudan flag is not a simple color switch of either of the other two. It’s a three-way swap of the Palestine flag and a four-way swap of the Arab Revolt flag.
Thanks for the additions, Ignotus and mbh, Appreciate them.
I’m not going to count Nova Scotia and Scotland. Any additional features rule them out. However, I did find this page on Flags of the World site that has all the flags that are based on saltires (i.e. X from corner to corner). Most of them have some additional feature, but there’s some without. In particular, I found a shipping line flag, that of Hong Kong, Canton & Macao Steamship Company, Limited is a white saltire on red, which is the swapped Alabama flag and the St Patrick’s cross flag. There are probably others on that page that are also switched-color flags (I’ve only checked a few of them).
Cuba is a 2:1 aspect ratio, and Puerto Rico appears more squared, so they aren’t identical. Nitpick of nitpicks, I know.
Qatar and Bahrain are very similar, but not identical. Different ratios, and the number of “spikes” is different, but they are otherwise different shades of red.
Except for a seal, Costa Rica and Thailand are similar.
Even weirdest is that Chad and Romania are identical, while Andorra is the same except for the ratio and a coat of arms.
South Sudan and Mozambique almost, the latter has an added hoe and AK-47.
That’s actually a color swapping, so point to you for that one. FotW doesn’t show any seals on their flags.
Flags of the World shows the blue in those two are different shades: ChadRomania
The basic plan is the same (ignoring the gun and tool): a triangle on the left with a yellow star in it and three stripes to the right separated by white borders, but the colors of those fields are all different. Mozambique has a red triangle and green, black and yellow stripes, while South Sudan has a blue triangle and black, red and green stripes.
If you want other identical flags, Indonesia and Monaco are the same.
I should elaborate: Costa Rica’s national flag has no seal, but their state flag does have a seal. I’ve never been quite certain of what the difference between national and state flags are, but no doubt they’re displayed by different people or at different times or something like that.
“state flag” or “government flag” is the flag legally authorized for use of government offices and official public-sector activities - the flag of the State. “national flag” or “civil flag” is a flag for general use by private entities, individual citizens and nongovernmental activities, the flag of the nation/people. In many countries in everyday use interchangeable use by civilians is authorized or there is little or no enforcement or the differences are so subtle they may become used indistinctly. Or else, as in the flags of the Central American nations, the mutual similarities are so great that you virtually have to use the state flag if you want to tell them apart. See here.
In the US historically the national flag, government flag, battle standard, naval ensign and merchant ensign have been all the same thing but in other places they are visiby different.
The Belgian flag is similar to the Germanflag, rotated, except that Germany is Black, Red, Yellow, and Belgium is Black, Yellow, Red. Also, Germany’s yellow is really gold. And proportions differ.
The flags in your link are purported to be French and Dutch , positing that one is identical to the other, merely rotated. In fact, the Dutch and French flags have a different shade of red. And a different shade of blue. And different proportions. But the white center stripe is the same, so there’s that.