Does anyone know much about this topic? I have a limited company and want to start something quite similar but want to avoid the cost of setting up a new company. Can i just use a different trading name as long as i include all accounts in with my existing company? Sorry to be vague but i don't want to give too much away but as an example, if i own abc company. Can i start something else and call it 123 company but just have it as part of abc company?

Many Thank Yous

I know many companies that trade in such ways so know it is possible - unfortunately do not know the ins and outs so speak with your accountant or companies house.

An example of a company I know:

There is one overall company. They used to have several separate organisations, each one an individual company in their own right.

So, they used to be:

ABC UK Limited (Main account)
XYZ Limited (subsidiary)
123 Limited (subsidiary)
DEF Limited etc (subsidiary)

They changed this to simplify accounts and effectively closed the subsidiares and now looks like this:

ABC UK Limited (Parent)
ABC UK Limited trading as XYZ
ABC UK Limited trading as 123
ABC UK Limited trading as DEF

One company with different trading divisions but only one set of account for companies house.

Hope that helps

Each limited company would need to be registered with Companies House + an annual registration fee, and have their accounts prepared and submitted by a qualified accountant each year. Limited companies have a string of rules and regs. to follow and just because the parent Company follows them does not mean that the subsidiaries can avoid them.
It can be a mine field but I would have a word with your accountant before going down this route.
Do all the businesses need to be limited companies?