Question: How long does eyeliner last until it expires?
Makeup used around your eyes tends to have shorter shelf lives than most other makeup products. This holds true for eyeliner, especially the liquid variety. Luckily eyeliner pencils last longer, as you can continually sharpen them to avoid contamination or the spread of bacteria.
If you are using liquid eyeliner pens or pots, be sure to dispose of them four months after they have been opened. If you are not sure how long you have had the product check to see if it has dried out or has an odd smell. This is a good indication that is has expired.