"Punctual payment" refers to the act of paying on time and as expected. There are several synonyms for this term that can be used in various contexts. "Timely payment" conveys the same meaning but emphasizes the importance of acting promptly. "Prompt payment" is also a common synonym and implies a sense of urgency in settling a debt or obligation. "Regular payment" suggests a consistent and reliable payment schedule. "Dependable payment" is another option that highlights the essential nature of timely payment in maintaining trust and stability in relationships both personal and professional. Ultimately, the choice of synonym depends on the context and desired emphasis, but each carries the same essential meaning.