Create Serial No. With Fill Series in Excel Creating sequential serial number manually is native. It’ll make you less productive in office. You can write automatic serial number excel formula but that will require you to add another step, converting formula result into value which is also a few clicks away. But there is a secret excel built-in feature called “Fill Series”. In this excel tutorial we’ll capitalize the fill series feature and create a sequential serial number from 1 to 1000 within