While creating list of real flags suitable as symbols for languages, I found two pairs of nearly identical flags: Nordic cross yellow, red (Norn and Old Norse) and Nordic cross green, yellow, blue (Low Saxon and Veps). I was aware of more "twin flags" (Monaco and Indonesia, Romania and Chad...), so I created this gallery to catch them. First I tried to show as many twins as possible, now I list only categories for striped flags. If some category contains only one flag, it should be removed from this list, unless it is Nordic Cross flag.

Terminology:

  • Twin = same shape, colors, order, different hues or proportions
  • Sibling = twin defaced with different emblem (Slovakia and Slovenia)
  • Cousin = switched colors within same shape or modified shape within same colors (e.g. rotation, fimbriation)

Flags are nested by colors in English alphabet order. Tricolor flags are nested by their first two basic colors. Basic colors are black, blue, green, red, white and yellow. But it is easy to find flag with desired color regardless of their order. Every tricolor category can contain six permutations of twins. Total number of possible twin flag sets with two or three stripes and six basic colors is 360. How many is used, I have no guess.

I recommend visit Flag Identifier by Ivan Sarajčić for creating "identikit" of flag searched (including twins). For Nordic crosses see also this list from FOTW.

Black and blue edit

Black, blue, brown edit

Black, blue, green edit

Black, blue, orange edit

Black, blue, red edit

Black, blue, white edit

Nordic cross:

Cousins:

Black, blue, yellow edit

Black and green edit

Black, green, orange edit

Black, green, red edit

Kenya and South Sudan are fimbriated cousins

Nordic cross:

Black, green, white edit

Nordic cross:

Black, green, yellow edit

Black and orange edit

Black and red edit

Black, red, black edit

Black, red, white edit

Black, red, yellow edit

Middle red stripe (cousins):

Proposals for Germany (cousins):

Olitopia (alternate history) is cousin

Red, black, red edit

Black and white edit

White cross (cousins):

Black cross edit

Black, orange, white edit

Black, pink, white edit

Black, white, black edit

Black, white, yellow edit

White, black, white edit

Black and yellow edit

Yellow cross:

Black cross:

Black, yellow, black edit

Yellow, black, yellow edit

Blue and green edit

Nordic cross:

Blue, brown, green edit

Blue, green, red edit

Blue, green, white edit

Green, white, blue:

Blue, white, green:

Cousins:

Blue, green, yellow edit

Green, yellow, blue:

Blue, yellow, green:

Blue and pink edit

Blue and red edit

Red saltire:

Blue, red, blue edit

Blue, red, white edit

Blue, white, red, white, blue with device

Blue, white, blue with diagonal red stripe

Nordic cross blue, white, red:

Cousins:

Cousins:

Blue border, white cross:

Halved white, blue, red:

Halved blue, white, red:

Red-white stripes, blue canton with white stars (siblings):

Quartered cousins:

Less than cousins:

Blue, red, yellow edit

Cousins:

Red, blue, red edit

Blue and white edit

White cross:

Siblings:

Nordic cross:

Cross from stars:

White saltire:

Siblings:

Blue cross:

Nordic cross:

Blue saltire:

Siblings:

Diagonal stripe:

Blue, brown, white edit

Blue, orange, white edit

Blue, white, blue edit

Two fictious countries:

Blue, white, yellow edit

Nordic cross white, yellow, blue:

Cousins:

Halved blue, white, yellow:

Diagonally divided:

White, blue, white edit

Blue and yellow edit

Yellow cross:

Siblings:

Yellow saltire:

Blue cross:

Blue saltire:

Blue, orange, yellow edit

Blue, purple, yellow edit

Blue, yellow, blue edit

Nordic cross:

  Baarn (Netherlands) has both striped and crossed cousins

Yellow, blue, yellow edit

Green and orange edit

Green and red edit

Cross:

Green, purple, red edit

Green, red, green edit

Green, red, white edit

Nordic cross green, white, red:

Cousins:

White left, red over green:

Vertically halved red, white, green:

Green, red, yellow edit

Red, green, red edit

Green and white edit

White Nordic cross:

Siblings (mostly saltires):

White device (siblings or cousins?)

Cousins:

Brown, green, white edit

Green, orange, white edit

Green, pink, white edit

Green, purple, white edit

Green, white, green edit

Green, white, yellow edit

Quartered per cross:

White, green, white edit

Green and yellow edit

Green cross:

Yellow cross:

Saltire:

Yellow harp:

Yellow crescent:

Green, orange, yellow edit

Green, pink, yellow edit

Green, yellow, green edit

Yellow, green, yellow edit

Grey and white edit

Maroon and white edit

Maroon, white, maroon edit

Orange and white edit

The third color of Hernandarias is maroon or purple?

Purple and white edit

Purple and yellow edit

Red and white edit

Nine stripes:

White cross:

Nordic cross:

Greek cross:

Maltese cross:

Saltire:

Red cross:

Siblings

Nordic cross:

Red saltire:

Siblings:

Quartered:

Per saltire:

White star:

Cousins:

Orange, red, white edit

Red, white, red edit

Red, white, yellow edit

Siblings:

Cousins:

White, red, white edit

Red and yellow edit

Centered cross:

Nordic cross:

Red cross:

Siblings:

Purple, red, white edit

Purple, red, yellow edit

Red, yellow, red edit

Nordic cross:

Yellow, red, yellow edit

Yellow sun on red background edit

White and yellow edit

Orange, white, yellow edit

Purple, white, yellow edit

Yellow, white, yellow edit

More than three colors edit

Black, green, red, white edit

White, red, yellow, black edit

Blue, red, white, yellow edit

Horizontally striped

Quartered 5173:

Cousins:

Meaning of numbers see here

Red-white stripes, blue canton with yellow crescent and star (siblings)

Nordic cross

Rainbow flags edit

Diagonal divided flags edit

Bonaire, Maruri-Jatabe

Quartered flags edit

Numbers of directions:

3 2 1
4 . 0
5 6 7

Blue, red, white, yellow

Flags containing flag of Ulster edit


I am vexillographer myself. If you want to see my initial list-of-twins design, write a note to me. It was much different and even now it is not perfect. If you have proposlas for another change, write to me. Now you can see more my pages (list is at my Indonesian user page).