How do traveller academics get reimbursed for accommodation shared with families?

Usually, you will explain the specifics of your travel and provide some documentation about

• the actual expenses for travelling with your family
• the expenses you would have had, had you travelled alone

You should then be able to make a case for getting reimbursed for the (lower) expenses listed in item #2, even though all your bills show the (higher) expenses from item #1.

If there was anything that cost the same, or even less, for the whole family compared to what you would have paid alone, make sure to provide good proof of the hypothetical 1-person-price and you might even get reimbursed some of what was used by the entire family :)

I have always eaten these cost differences. My family is small (me and wife), and I always get a room with a king bed anyway. We pay the cost for my wife's flights, the university (maybe through grants) pays for my flights, per diem, and hotel. If there is a rental car required, it doesn't change size, so the university pays that as well.

I don't think that the university would pay the difference for anything I chose to make different for my work travel (extra stops, room for children, etc.), because I think there are either university rules or granting agency rules that prevent it. These are my choices to travel with family, I must make up the differences.