At One Place

Does Paint expire?

Does Paint expire?
Unopened water-based paint keeps a few years; opened tins depend entirely on how well they were sealed.
Unopened emulsion: 2-5 years. Unopened solvent-based: up to 10. Opened: 1-2 years if properly sealed

Water-based paint is an emulsion, and what kills it is either freezing — which breaks the emulsion irreversibly — or the water evaporating past a partly sealed lid. Solvent-based paint lasts longer unopened but skins over quickly once air is in the tin. A skin on the surface is not itself failure: cut round it, lift it off and check what is underneath. Paint that has separated will usually recombine with thorough stirring, but paint that smells sour or rancid has grown bacteria and will not.

How to store it

  • Seal the lid by tapping round the rim, and store the tin upside down so the paint itself makes the seal.
  • Never let emulsion freeze. A garage in a cold winter destroys more paint than time does.

How to tell it has gone

  • Sour or rancid smell means bacterial growth — discard.
  • Lumpy, cottage-cheese texture that will not stir out means the emulsion has broken.

"Use by" and "best before" are legally different. Use-by is a safety date and should be respected; best-before is about quality, and food is usually fine well past it. Where the two diverge matters, the page above says which applies.

Common questions

Does Paint expire?
Unopened water-based paint keeps a few years; opened tins depend entirely on how well they were sealed.
How long does Paint last?
Unopened emulsion: 2-5 years. Unopened solvent-based: up to 10. Opened: 1-2 years if properly sealed

Related pages

Sources

  1. Official vendor product documentation — At One Place

How these figures are compiled and checked