Thanks @ClubMan, I had a look at that previously but wasn't clear as to an actual refund was possible as it just mentions offsets. For a company with one income stream (for example, a butcher's shop), there's no additional income stream to offset against. In that scenario, where Revenue say "Those companies can offset a trading loss against their total profits of the immediately preceding accounting period", is it possible to get a refund of the corporation tax paid for the immediately preceding accounting period? If not, what exactly does that offset consist of in real terms?
This sentence is referring to companies carrying on an 'Excepted Trade'. These are trades taxed at 25% where the source of income is from dealing in or developing land, minerals and petroleum activities.