There is no rule on the process of billing a translation.
Translation can be billed by word, page, hour, day, etc.
The current international standard currently in the world is to bill in words.
(From French to English billing is 0.09 EUR per word and English to French
We are at 0.07 EUR-word (Source: Proz.com which is a reference in the field) Some countries charge per page. Each formula has its advantages and disadvantages. It should be noted, for all intents and purposes, that a normal page contains between 250 to 300 words.

In Superlingua, we find it important to analyze each document before listing. We work to give adequate prices to our customers. Our pricing policy is based on the following elements: The number of words, the terminology used, the formatting of the document, the number of tables or graphs, the deadline etc …
If billing per page … All this allows us to meet the delivery times that are based on the above factors.

We charge an Interpreter / day.
The price depends on the complexity of the terms that will be discussed, the number of days.
There is no half-day in our billings given the commitments made by our consultants to make themselves available exclusively for the event.