This is the date on which the contract was concluded or the date on which the contract enters into force economically, unless otherwise specified in the contract. In addition, a contract is deemed valid only when all the necessary parties sign it. For example, if the effective date of the lease is September 1, but today is September 3 and the necessary parties have not signed the contract, it is not valid. Here is the general rule of departure dates: the duration of a contract begins from the date of entry into force of the contract. Unless otherwise stated in the contract, the effective date is normally the date of performance – the date of signature of the contract. If you have different parties who sign different data, the contract takes effect on the date that was signed by the last signature of the party. Such a delay in meetings is often due to logistics. For example, if the closing date of a transaction is a day or two from the scheduled date, the parties may prefer not to change the date in each of the transaction documents. And if one party signs a contract on a given day and then sends the contract to the other party for signature by mail, the date in the introductory clause could be the day the first party signed or another date. When signing your next contract, take the time to read the document in depth. Now that you know the difference between a validity date and a run date, watch the document to see exactly when it will come into effect. To understand the difference between signing a contract and entering into force of a contract, there are two important concepts to know: date of entry into force and date of performance. .