Paint's Shelf Life. The shelf life of paint depends on the type and whether the paint container has been opened. Solvent-based oil or alkyd paints can remain usable for up to 15 years if they were never opened and always kept away from temperature extremes. Water-based acrylic and latex paints can stay good for up to 10 years if never opened and kept from freezing. Leftover paints that have been opened should be closed up tightly, stored in a cool, dry place and used within two years.