Do Boxed Mashed Potatoes Ever Really Go Bad? - Tasting TableUnopened instant mashed potatoes last 1-2 years; opened ones should be consumed within 2-3 months for best quality.
The Worst Instant Mashed Potatoes Taste More Like The Box They're Sold In - Tasting TableQuality varies significantly between instant mashed potato brands; some are far from homemade quality.