Hi Lill,
I'm inclined to agree with @Mollcons. I'm only new to QuickBooks Online, but I've used QuickBooks Desktop for years. So far I've not seen a whole lot that Online can do that Desktop couldn't and I've certainly never submitted our Companies House returns using QB Desktop. I don't even see how it could do that since it doesn't contain the kinds of information the CH return requires -- things like number of issued shares, share transfers, names and addresses of Directors, and so on.
As I say, that's all for the desktop version, but I'm pretty sure QBO is the same.
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