"It's about time" is an expression that refers to an event or action that should have happened sooner. There are a variety of synonyms for this phrase, including "at last," "finally," "about time," "long overdue," "high time," and "overdue." These words can be used in different situations, depending on the tone and context of the conversation. Some synonyms might be more appropriate for formal or professional settings, while others may be more suited to casual or friendly conversations. Regardless of the situation, these words provide a useful way to express a sense of relief or urgency in response to a long-awaited event.