870。 The real interest rate of postal loans of Postal Bank is 5%, and the annual interest rate of postal loans is between 4.35% and 7.05%. Suppose the user borrows 20,000 yuan from the postal loan, and the annual interest rate of the loan is 4.35%, so the interest for one year is 870 yuan. Postal loan of Postal Savings Bank is an online personal consumption credit loan product with high quota and long term, which can solve the large capital turnover needs of most users.