To ask how you split costs on a big family holiday?

[tryingtoplanaholiday]

My mum and dad both have big birthdays coming up so I want to suggest that we go on a big family holiday with the whole family. (This will likely be in 2027, to give everyone time to save)

I haven’t suggested it yet because I’m a bit split on how we would share the costs.

Our family is as follows

parents, me, a younger sibling (both me and my younger sibling are single, no children), and my older siblings who are each married with two children a piece.

We would likely end up needing 7 or 8 bedrooms (depending on which children would be happy to share), so how is it split? Is it an even split per family, which would mean my brother and I end up paying huge chunk more because of the extra bedrooms, or is it per bedroom? So i would pay for one bedroom of the accommodation and the families using two pay for two?

I want to have it laid out before i suggest it because otherwise i can see it being absolute chaos.

YABU - everyone pays an equal split. It’s a family holiday and it shouldn’t be unequal.

YANBU - you should pay per bedroom

We book a house with 15 rooms for the weekend every year (different house each time). 5 of the rooms are for single occupancy.
it's always split per double room. Any other way causes a headache and isn't fair.
some of the doubles are slightly larger and can fit an extra bed for a child, the cost is the same. However, if one of the rooms happened to be a single (we haven't come across this yet) then we would probably reduce the cost of it.
food etc is split per person with the children paying half.
It always works out well 🤗