The most common substitute for sherry vinegar is wine. Either red or white wine may be used as long as it complements the other ingredients in the recipe. If the acidic properties are more important to the recipe than the sherry flavor, using another vinegar is a better choice.
By European law, sherry is a protected designation and only products produced in the Spanish province of Cadiz may be legally labeled as sherry. As a result, authentic sherry vinegar is always from Spain. While other European wine vinegars such as balsamic are increasingly popular in the United States, sherry vinegar is less commonly imported.