Hello Paul, I am Keith, one of the experts on Just Answer, and pleased to be able to help you with your question.
In a word yes they do. If you are involved in more than one business activity then expenses should offset each individual area and then finally be pooled. Remember that certain capital items [eg a new car for business use] do not qualify as expenses at all, but must go through the Capital Allowance regime. Which have an excellent summary here:
If you have paid employment also then if you make self employed losses these may be used to offset employment or indeed other income or carried forward if desired.
I do hope that my reply has been of assistance.
That is no problem so he just declares a loss; it is not uncommon. When the cash comes in it will all come out in the wash as it were next tax year as he uses the brought forward losses to reduce his profits for tax.
Remember that computers are capital allowance items and only that is chargeable against tax, but currently the Annual Investment Allowance (AIA) allows such expenditure to be run off against tax at 100%.
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