This is what Britain's next flag could look like

What would happen to the Union Flag if Scotland were to vote for independence?

No one knows for sure, but the Flag Institute has passed on some suggestions to i100.

The UK's national charity for flags surveyed its members and others about the future of the flag ahead of the referendum - and received its "largest postbag ever".

"As the UK's national flag charity the role of the Flag Institute is to facilitate and inform any national debate about its flag - nothing more complicated than that," the Flag Institute's chief executive Charles Ashburner.

Here are 12 of the best suggestions from the public.

1. This design exchanges the blue of Saint Andrew's Cross with the black of the flag of Saint David, the patron saint of Wales.

2. Other designs went further and included both black and gold from the Saint David flag.

3. Some suggestions included replacing the Saltire with elements of the Welsh flag.

4.

5. This suggestion is more Wales-orientated.

6. This unique design is by John Yates and titled 'United Britain'.

7. Other designs join the flags of the remaining home nations together.

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10. Others include coats of arms.

11. Some emphasise the monarchy.

12. While this includes symbols representative of the different home nations.

More: These are all the flags that might have to change if Scotland votes 'yes'

More: This flag shows just how much the UK loses without Scotland

More: The eight weirdest flags the world has ever seen

All images courtesy of the Flag Institute.