"Falls on" is a frequently used phrase to describe an event or occurrence happening on a particular day or time. However, there are numerous synonyms that can be used instead of "falls on" to add variety and nuance to your writing. Some of the synonyms for "falls on" include transpires, occurs, takes place, materializes, happens, comes about, eventuates and transacts. By utilizing these synonyms, you can enhance the overall quality of your writing and avoid repetition of a single phrase. It is essential to have a wide range of vocabulary and synonyms to make your writing more compelling and engaging for the readers.