The beginning of fall in the Maltese archipelago brings visitors to the velvet season. Tours to Malta in September are still very popular. The heat subsides and the water is warm for at least two more months. Diving near Gozo is ideal and all the seaside resorts are open and offer good beaches.
That said, prices for a vacation in Malta in September are slightly lower than summer prices. Although slightly higher than they will be in the off-season or winter. Holidays in Malta in the fall can already be and excursion, at this time the sun is not so active, although in September it is still worth hiding from it at noon. Go to Sliema or Valletta, go to Mdina.