Rome and Milan are Italy's two largest cities and the only two with deep enough international school markets to absorb a relocating family at scale. The choice between them is less about schools (both are credible) and more about the broader urban personality and the specific industry posting that brought you to Italy.
Schools
Both cities host credible international schools. Rome's market is smaller and more diplomatic-oriented (St George's British International, the American Overseas School of Rome, Marymount International). Milan's market is larger and more corporate (American School of Milan, International School of Milan, Sir James Henderson, St Louis School). Fees in both are EUR 16,000 to 26,000 for senior years.
The industry split
Milan is Italy's commercial capital. Finance, fashion, manufacturing, design, advertising. Most corporate postings into Italy land in Milan. Rome is the political, diplomatic and historic capital. Most diplomatic and government-adjacent postings land in Rome. Each city's expat community reflects this.
Housing and lifestyle
Rome housing is materially cheaper than Milan but the rental market is less responsive (older buildings, slower turnover). Milan housing is more expensive but the supply is more dynamic. Both cities have walkable family neighbourhoods.
The decision
Choose by the posting. If your work is in Milan, Milan. If your work is in Rome, Rome. Both cities deliver credible international schooling; the city personality matters more than the schools.