I would maximize the expenses on the company that had the profit to avoid or reduce your Self-Employment taxes and get the non-profitable business as close to breakeven as possible.
As the expenses can only be deducted once, posting a portion of them (posting them) on the non-profitable company will only increase that loss. Self-Employment taxes are based on a % of the profit and will always be $0 on a company with a loss. On the other hand, the company that has a profit FICA / Self-Employment taxes, as a % of those profits. You cannot offset the losses from the "non-profitable" against the profitable business, when calculating Self Employment taxes, each business stands on its own. So, you will wind up pay extra self-employment taxes on the profitable business.
Your justification can be that the non-profitable business could not afford to pay these bills, s the profitable business covered them.
