Straight-Line Method of Amortization

Written by True Tamplin, BSc, CEPF®

Reviewed by Subject Matter Experts

Updated on March 09, 2023

Straight-Line Method of Amortization: Definition

The straight-line method of amortization allocates the discount evenly over the life of the bond. There is a constant interest charge each period.

An entry is usually made on every interest date, and if necessary, an adjusting journal entry is made at the end of each period to record the discount amortization.

Application of the Straight-Line Method

To demonstrate the use of the straight-line method, we will return to the Valenzuela Corporation example.

In this case, the discount of $7,024 is amortized over 10 interest periods at a rate of $702 per interest period ($7,024 / 10). The total interest expense for each period is $6,702, which consists of the $6,000 cash interest and the $702 amortized discount.

Another way to calculate the $6,702 is to divide the total interest cost, $67,024, into the 10 interest periods of the bond's life, as in the journal entry for 1 July 2020. The same is done for each subsequent payment date.

To record cash interest payment and amortization of discount

As the bonds approach maturity, their carrying value increases. The result of this, as well as subsequent entries, is to reflect the increase in the carrying value of the bonds.

This is attributable to the discount account, which is offset against bonds payable in arriving at the carrying value (this decreases every time a credit entry is made to that account).

To illustrate, the relevant T-accounts and a partial balance sheet as of 1 July 2020 are presented below.

T-Accounts For Bonds Payable and Interest Expense
T-Account For Discount On Bonds Payable
Partial Balance Sheet

In each interest period, the bond's carrying value increases $702, so that by the time the bond matures, the balance in the Discount on Bonds Payable account will be zero, and the bond's carrying value will be $100,000.

Exhibit B below shows an amortization schedule for this bond on the straight-line method. When the company repays the principal, it will make the following entry:

Journal Entry For Principal Repayment
Discount Schedule Using Straight-Line Method of Amortization

Exhibit B

Straight-Line Method of Amortization FAQs

About the Author

True Tamplin, BSc, CEPF®

True Tamplin is a published author, public speaker, CEO of UpDigital, and founder of Finance Strategists.

True is a Certified Educator in Personal Finance (CEPF®), author of The Handy Financial Ratios Guide, a member of the Society for Advancing Business Editing and Writing, contributes to his financial education site, Finance Strategists, and has spoken to various financial communities such as the CFA Institute, as well as university students like his Alma mater, Biola University, where he received a bachelor of science in business and data analytics.

To learn more about True, visit his personal website or view his author profiles on Amazon, Nasdaq and Forbes.