IB interest calculation?

Discussion in 'Interactive Brokers' started by lsudaytrade, Jan 6, 2008.

  1. getting a little confused with the calculation.

    lets pretend John day trades and has $200K cash in his IB account.

    at a 4.25% benchmark rate(1/3/08).

    to me it looks like John accrues per day:

    Tier Balance
    <10,000 interest = 0.00
    10K-100K interest = 9.375 [90K x (4.25%-0.5%)/360]
    >100K interest = 11.11 [100K x (4.25%-0.25%)/360

    thus $20.485/day


    can someone confirm on how this is calculated?
  2. I tried your calculation using my last statement. Using the prior day's settled cash and your calculation, I was a bit off. I did it again using 365 days (instead of 360) and got within 1 cent.