Each party has a certain rights and duties to fulfill. The question of when a contract must be performed is an important factor. Many contracts call for a specific time by which the agreed-on acts must be completely performed. In addition, many contracts provide that time is of the essence. This means that the contract must be performed within the time limit specified. A party who fails to meet the deadlines specified in the contract is liable for breach of contract.

When a contract does not specify a date for performance, the acts it requires should be performed within a reasonable time. The interpretation of what constitutes a reasonable time depends on the situation. Generally, unless the parties agree otherwise, if the act can be done immediately, it should be performed immediately. Courts sometimes have declared contracts to be invalid because they did not contain a time or date for performance.

 In Illinois, a deed or contract executed on a Sunday or legal holiday is valid and enforceable. However, when the last day on which a deed or contract must be executed is a holiday or Sunday, the deed or contract may be executed on the next regular business day.