It is easily prepared in the laboratory by treating sodium metal with absolute ethanol:[3] The reaction of sodium hydroxide with anhydrous ethanol suffers from incomplete conversion to the ethoxide, but can still produce dry NaOEt by precipitation using acetone,[4] or by drying using additional NaOH.

[6] Sodium ethoxide is commonly used as a base in the Claisen condensation[7] and malonic ester synthesis.

In practice, the alcohol/alkoxide solvating mixture must match the alkoxy components of the reacting esters to minimize the number of different products.

It has been reported that even newly-obtained commercial batches of sodium ethoxide show variable levels of degradation, and responsible as a major source of irreproducibility when used in Suzuki reactions.

Further reactions lead to degradation into a variety of other sodium salts and diethyl ether.