Can you use epoxy over stained wood?

Yes, though the effectiveness varies depending on the type of stain used.

Alcohol-based and water-based stains are ideal and dry fast. An epoxy coat can go over them in about 24 hours.

Note: This is meant to be general advice. Some niche products may be uniquely different from the average stain of these types and cause unforeseen issues.

Oil-based stains such as Minwax will take a very long time to fully dry. If an oil-based stain is used, you must apply a clear oil-based polyurethane to seal the surface before applying a seal coat of our UltraClear table top epoxy. If you pour epoxy directly onto the oil-based stain before it has dried completely, the epoxy may end up not bonding properly and could peel off months later.

Note: Even with two or three coats of oil-based polyurethane, you'll still need to apply a seal coat of epoxy; don't skip that step. The poly does not seal the wood adequately to prevent air bubbles from forming during the epoxy flood coat phase.

You can learn more about how to apply a seal coat here.