I saw this phrase while I was reading an example of the usage of an adjective on Cambridge dictionary online i.e. included. This is the provided link: included. The complete sentence is:
The trip cost a total of £250, insurance included.
Why is it not:
The trip cost a total of £250, insurance is included.
Again, another example:
The fee covers everything, babysitter included.
Why again is it not:
The fee covers everything, babysitter is included.
Insurance and babysitter are nouns and included is an adjective, so why is this allowed? What I'm familiar with is adjective+noun and I've never seen noun+adjective before.
Best Answer
I would say "insurance included" or "babysitter included" are examples of participial phrases: they use a participle to describe something about the main sentence. Participial phrases are very common in English. For example,
You can see how the participial phrase is not the main action of the sentence, but it tells us something about the main action.
In contrast, insurance is included or babysitter is included are complete sentences, because they have a subject (insurance/babysitter) and a main verb (to be). You can't just ram two sentences together with a comma between them; this is an error in English called a comma splice. You could join them with a conjunction, like
or