The SEC has a formal definition of penny stock (under $5/share, not listed on a national exchange that meets specific size standards, and not from an issuer with sufficient net tangible assets or revenues). In everyday usage, penny stocks are speculative micro-cap and nano-cap names — often biotech, mining, crypto-adjacent, or pre-revenue shell companies — characterised by low share price, low float, low average daily volume, and high volatility.
Most penny stocks trade on the OTC Pink tier, though sub-$5 names also exist on Nasdaq and NYSE (some of which carry continued-listing risk if the price stays below $1). 'Optionable penny stocks' is a specific niche: a small set of low-priced names that maintain enough float and liquidity to support listed options.
Broker selection matters more for penny stocks than for any other equity segment. Order routing, short-locate quality, sub-penny pricing limits, PFOF (payment for order flow) practices and the ability to use direct-market-access routing all materially affect outcomes for active traders. The buystock.net broker matrix singles out day-trader specialists (TradeStation, Cobra, CenterPoint) and penny-stock-friendly mainstream brokers for this audience.