After-hours trading is the buying and selling of securities outside the regular hours when exchanges are officially open. Regular US stock market hours are 9:30 a.m. to 4 p.m. Eastern Time, but some brokers allow trading before and after these hours. After-hours trading typically has lower volume and wider spreads.
If a company releases earnings news after the 4 p.m. market close, investors can react to the news by trading after-hours from 4 p.m. to 8 p.m. However, they might find fewer buyers and sellers available, so they could face wider bid-ask spreads and less certainty about execution.
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