Coinmarketcap uses Upbit for 98% and Bittex for 1%, but deposits and withdrawals are disabled on Upbit. The SBD price on Upbit is $0.85 right now, but on Bittrex it is $1.00.

See https://coinmarketcap.com/currencies/steem-dollars/markets/

Also see https://steemblockexplorer.com on the top right of the page. (calculated using the Steem internal market).