# Flat interest calculation

### Flat Interest Calculation

The flat interest method calculates interest on the loan amount (principal) for the term of the loan account. The interest and principal components of all repayments is the same for the life of the loan account.

The calculations are:

Interest = P * r/100 * n

Interest Installment = Interest / number of Repayments

Principal Installment = P / number of Repayments

Payments = Interest Installment + Principal Installment

Where,

P = loan amount (principal)

r = rate of interest per period (e.g., per year, per month)

n = term of the loan

**Example**

A client borrows $1000 (P) with a interest rate of 2% (r) per month for four (n) months with four monthly payments.

Interest: $1000 * 2/100 * 4 = $80

Interest installment: $80 / 4 = $20

Principal installment: $1000 / 4 = $250

Monthly installment (principal and interest): $20 + $250 = $270

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