I have only seen this being done for football players that have running contracts that will expire in a year's or two year's time and want to make it easy for the next football club to sign them afterwards, but I have never seen it in other industries so I don't know if it's common. My question is: is it common or wise to sign a pre-contractual agreement with a potential future employer so that one agrees to sign a contract in a year's time, after the current contract with the current company expires? If so, what are usually the clauses of such pre-contracts in the UK?
Reliance upon a pre-contractual agreement would be wrong in your circumstances. You must enter into proper contract with your existing and future employer.The same is legally possible in UK and elsewhere. Consult a good lawyer/law firm of your choice.
Under the laws of England and Wales, pre-contract agreements areThe clause has no binding effect.
usually marked as ’subject to contract’ or worded similarly. Such an
agreement is usually held to be no more than a mere “agreement to
agree” something further in the future. As such, the agreement
usually has no binding effect under normal established contractual
principles. (taken from the article you linked to)
I would say its not very wise to use it. It complicates a contract and thus increases the risk of misunderstandings or loop holes for no benefit. As far as I know its not common. I have never heard of it before.