Such a simple question...but...it depends (sorry)!
The general rule of thumb is that if you can relate the cost to the generation of revenue, it can be claimed.
Different expenses for different businesses
The deductibility of an expense will often depend on the nature of your business. For example, a media production company could claim subscriptions for Netflix and Sky TV, but a construction business could not.
We have our list of claimable (or not) expenses here.
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Just get in touch with with us at firstname.lastname@example.org if you need to be sure, given your circumstances.