Does Rosin Expire?

While there isn’t an expiration date on rosin, it does gradually dry out overtime which will affect the way it performs. The consistency of rosin directly effects the way that the maker intended it to work, so if you want to maintain those playing qualities, we recommend replacing your rosin every 1-2 years.

It is very unlikely that you will go through an entire cake of rosin in that time, so writing the purchase date somewhere on the packaging is a good idea, or perhaps even setting a reminder in your phone.

Incidentally, many players end up breaking their rosin before it expires (quite very common occurrence because rosin is so brittle). If this happens to you, please do not glue it back together or melt it back together using a flame. Glue can get stuck in your bow hairs, and Rosin turns into hot lava when heated and can give you a very severe burn! It’s much wiser to simply replace your rosin with a new block. 

Next: Can rosin damage my instrument or bow?