I would guess (technically) at least an 11x11 so that you would have at least 5ft. of space around the table. However, we have a 60" round table in our 12x12 breakfast nook and it feels very comfortable. We probably wouldn't have wanted it any smaller. So if you have a choice, I would say at a 13x13 or 13x15 space (especially if you'd like to include a console/credenza in the space).

Thanks so much.