Has there ever been a 15–5 in all competitions?

Never.

It would be a scorigami. Based on the average number of goals in all competitions, the chance of a game ending 15–5 is about 1 in 536,748,792,327.

Nearby scores

1. 16–4 Never
2. 16–5 Never
3. 16–6 Never
4. 15–4 Never
5. 15–5 Never
6. 15–6 Never
7. 14–4 Never
8. 14–5 Never
9. 14–6 Never