Celsius (referral link) has increased its interest rate for Bitcoin from 5.1% to 6.4%, which now beats the rate of 6.2% from BlockFi (referral link). Note that though both rates quoted are annual interest rates, the BlockFi rate is compounding while the Celsius interest rate only accrues on the principal. This may matter to you if you plan on keeping your balance deposited for extended periods of time (more than a year, for example).

If you are thinking that you may be able to just withdraw the entire balance from Celsius and redeposit it to earn interest on the entire balance, beware that someone on Reddit claims that Celsius “remembers” your past interest balance and prevents this. Let me know in the comments if you have validated whether this is the case.

May 20, 2019 Update: Celsius rate decreased from 6.4% to 4.5%, check out Highest Interest Bitcoin Accounts for up-to-date rates