Entry and fees: Neither asks for a minimum deposit. Bitstamp charges 0.30% maker and 0.40% taker on its base tier, with discounts from $10,000 in volume; SEPA deposits are free of charge. Gemini quotes 0.2% maker and 0.4% taker through ActiveTrader, but a 1.49% convenience fee on simple buys. So how you buy decides it: through ActiveTrader Gemini is cheaper, through a simple buy it is markedly more expensive. Gemini itself lists needing the ActiveTrader platform for lower fees as a drawback.
Products and platforms: Both focus on the core business rather than derivatives. Bitstamp lists Bitcoin, Ethereum, altcoins and staking across web, app and Bitstamp Pro, and quotes high liquidity on the major trading pairs; its coin selection is smaller than at larger exchanges. Gemini lists Bitcoin, Ethereum, altcoins, staking and its own regulated stablecoin, the Gemini Dollar (GUSD), across web, app and ActiveTrader, plus Gemini Earn for staking yields. Its altcoin range is likewise smaller than Binance or Gate.io. Neither offers options.
Profile and verdict: Bitstamp (4.1/5 from 1,500 reviews) was founded in 2011, sits in Luxembourg, is CSSF-regulated and cites a strong security track record with no major hacks since 2015. Gemini (4.2/5 from 1,800 reviews) was founded in 2014, sits in New York, is regulated by the NYDFS and FCA, is SOC 2 certified and cites insured deposits. For European investors who want EU regulation and free SEPA deposits, Bitstamp is the natural choice; if you will use ActiveTrader and value US regulation and GUSD, Gemini serves you well.