You are able to claim the full cost of computer components below £500, for example, computer parts, printers, fax, mouse, keyboard, etc. as long as they are wholly and exclusively for business purposes.
Anything above £500 could be a fixed asset, in which case your account manager will need a copy of the invoice or details of; the asset, cost, type, date, etc.
If you purchase different components, that are effectively all one asset, that all appear on one bill for more than £500, then this could be classed as one fixed asset. For example, if you buy a monitor, keyboard, mouse, extra memory, cables, etc.. then this could be considered as one workstation and therefore one asset.
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