How many time zones does France span, counting its overseas territories?

How to get close to this number

The question tells you where to look: overseas territories. Metropolitan France sits in one zone, so any large answer must come from possessions scattered across the Caribbean, the Indian Ocean and the Pacific. Counting oceans rather than land is the route to the answer.

That is why this country beats the ones people would name first. Russia and the United States are physically wider but their territory is contiguous or nearly so; a country with small possessions spread across every ocean covers more longitudes than a country with a single wide landmass. Span is about distribution, not size.

It is worth noticing what the record actually measures: colonial history. Every territory contributing to this count is a remnant of an empire, so a time-zone superlative is really a map of where a country planted flags two centuries ago. Geographic records of this kind frequently encode political history rather than geography.