Polyx

Polyx is a centralized exchange launched in November 2018 in Estonia, combining crypto trading, a self-custody wallet and fiat on-ramps in one platform under EU authorization for crypto exchange and wallet services. It supports BTC, ETH, USDT and other major assets, charges a flat 0.1% fee regardless of maker or taker role, accepts card and bank-transfer deposits, and markets a deliberately simplified trading flow with assets held by users themselves.

Polyx was acquired by UK-based Bitcoin services firm SatSimple in February 2020. After a long silence, trackers marked the exchange as defunct in mid-2024 when its origin server stopped responding. The site has since returned with a P2P trading desk, an instant swap module and a self-custody wallet where users set their own ad conditions and choose payment methods, with trades settled through escrow scripts and private keys kept on their own devices.