Bonjour to bonsoir: At what time should one switch?

An article in newspaper Le Figaro has attempted to find a definitive answer to the problem, which, it says, could potentially see you address a friend with bonjour, but hear a somewhat defensive bonsoir in return. “Awkward”, it says.

One of the major differences is that bonsoir can be used to say “goodbye”, whereas bonjour never is.

The Guide du Savoir-Vivre by Marie-France Lecherbonnier adds that while it makes sense to add titles to the word bonjour - such as Madame or Docteur - doing so with bonsoir feels overly formal.

Originating in the 15th century, bonsoir comes from the latin “bonus serus”, meaning “good” and “later” so means not only saying goodbye to someone, but also wishing them a good evening.

And yet, the article continues, the definition of when the evening begins is subjective, especially between countries and cultures, when the concepts of “an early morning” or an “early dinner” can vary significantly.

It asks, whether evening begins at the end of the afternoon, or only once the sun begins to set - with this latter depending, of course, on the time of year?

Despite such potential social minefields, the article concludes that the use of the word bonsoir instead of bonjour is acceptable at any point after which you believe the day to be “in decline”.

In general, once most people begin to leave work - between around 17h-18h - the use of bonsoir is perfectly acceptable.

Similarly, conversations at this time of day can begin with bonsoir, and end with its feminine equivalent, “bonne soirée”, which effectively closes off the discussion and stands in place of “goodbye”.

However, a friendly bonjour - even if said after dark - will never be seen in a negative light.