Has there ever been a 12–0 in the Primera Argentina?

Yes, 4 times.

The first time: June 11, 1903, Barracas Athletic beat Flores Athletic (Flores Athletic 0–12 Barracas Athletic).

The last time: October 26, 1986, Argentinos Juniors beat Talleres (Argentinos Juniors 12–0 Talleres), 39 years ago.

Home wins: 3. Away wins: 1.

Nearby scores

1. 13–0 Never
2. 13–1 1 time
3. 12–0 4 times
4. 12–1 1 time
5. 11–0 4 times
6. 11–1 3 times

All games

1. October 26, 1986 Argentinos Juniors 12–0 Talleres
2. June 21, 1908 Alumni 12–0 Reformer
3. May 7, 1905 Quilmes 12–0 Reformer
4. June 11, 1903 Flores Athletic 0–12 Barracas Athletic