Taxation of Bond Income

There are 2 ways to earn money from a bond: interest and capital gains. Interest and short-term capital gains are taxed as ordinary income, while long-term capital gains are generally taxed at a lower rate. While this is simple enough, bond taxation is complex because there are several considerations that require different tax treatments, especially if the bonds were purchased in the secondary market:

This article discusses the general principles of the taxation of bonds. There are many specific rules in the tax code regarding bonds, especially for bonds that were issued or bought before 1994, but most of these rules result in only minor changes from the rules that apply today.

All bonds earn interest, which is taxed as ordinary income in the year when it is earned, whether or not it was actually received. Imputed interest is interest that is recognized as income but that was not received by the bondholder, and is the result of the bond either being issued at a discount or bought at a discount in the secondary marketplace.

If the bond is sold before maturity or bought in the secondary market, there may be a capital gain or loss that is recognized in the year when the bond was sold or redeemed. However, imputed interest will invariably lower any capital gains or increase capital losses.

Tax Update: Brokers Are Required to Report Cost Basis of Bonds

Beginning January 1, 2014, brokers will be required to report the cost basis of bonds and options. Brokers are already required to report the cost basis for stocks and mutual funds. However, the new rules will only apply for bonds purchased in 2014 and thereafter. Hence, the taxpayer must maintain records of bonds that were purchased before then.

Coupon Bonds

The simplest case of bond taxation is that of coupon bonds purchased for par value. Because all of the interest is paid periodically, there are no imputed interest complications. The taxpayer simply pays ordinary income tax rates on the interest received. However, there will be imputed interest if a coupon bond was bought at a discount in the secondary marketplace.

Imputed Interest for Original Issue Discount Bonds

Original issue discount (OID) bonds are bonds that were issued at a discount to the face value of the bond. The reason why this occurs is because it takes a certain amount of time after the coupon rate has been determined to get regulatory approval for the bond issue. In that duration, interest rates may have changed, forcing the issuer to sell the bonds at a discount if interest rates rose in the interim.

Stripped bonds or stripped coupons are also treated similarly, since they pay no interest and are issued at a discount. Note that this differs from market discount bonds, which are bonds that were bought in the secondary marketplace at a discount. The difference between the face value of the OID bond and the discounted offering price is treated as interest, which is prorated over the term of the bond and taxed annually, even though the bondholder does not actually receive this interest annually, but receives it as the difference between the face value and the issue price when the bond matures. Because OID interest is not paid as interest by the issuer, tax law refers to this type of interest as imputed interest. Tax law also makes a distinction between the imputed interest attributable to the original issue discount and the imputed interest attributable to a market discount, so hereafter the 2 will be distinguished as OID interest and market discount interest. In most cases, the taxpayer does not have to calculate OID, since the broker or the issuer must send the bondholder a Form 1099-OID that will have the amount of OID earned for the year in Box 1. In some cases, however, the taxpayer may have to modify that amount.

Original Issue Discount = Redemption Value – Issue Price

OID also accrues daily, so that the bondholder's adjusted basis is increased by the amount of the accrued OID, which can be approximated with the following formula:

Accrued OID (Current Date – Issue Date) in Days
(Maturity Date - Issue Date) in Days

Accrued interest is determined according to accrual periods, which are generally 6 months long, with one of those periods ending on the maturity date. If the bond is a coupon bond, then accrual periods begin or end on the coupon payment dates. The OID interest is calculated by the constant yield method:

Constant Yield Method
OID per
Accrual Period
=Price at Beginning
of Accrual Period
×Yield to Maturity
Number of Accrual Periods in 1 Year
Stated Interest Allocable
to the Accrual Period

Note that the yield to maturity (YTM ) is for the accrual period, so if the yield to maturity is 12% compounded semiannually, but the accrual period is 6 months long, then the YTM is half of that, or 6%. Note also that the price at the beginning of each accrual period is increased by the amount of the OID allocated to the previous accrual period. The stated interest is the interest that is actually paid by the issuer, which in most cases, is simply the coupon payment.

In most cases, the sale or purchase of a bond will not be at the beginning or end of an accrual period, so it will be necessary to calculate the daily OID, which is then multiplied by the number of days in the short accrual period:

Daily OID Formula
Daily OID =Price at Beginning
of Accrual Period
×Yield to Maturity / Number of Accrual Periods in 1 Year
Number of Days in Accrual Period

However, no OID interest is reported for:

OID is also reported as interest for certificates of deposits, time deposits, or other savings accounts with a term greater than 1 year if interest is only paid at maturity. For inflation-indexed debt instruments, such as Treasury inflation-protected securities, increases in the principal amount because of inflation are also treated as OID. if the principal decreases because of deflation, then this can be used offset the interest earned during the tax year.

Form 1099-OID

Imputed interest of more than $10 earned from securities should be reported by the broker or issuer on Form 1099-OID. However, the OID interest must be calculated for a stripped bond or coupon or if the bond was purchased for a premium.

Market Discount Bonds

If a coupon bond is sold for less than par value in the primary market — usually because market interest rates were higher than the coupon rate — then there will be some imputed interest proportional to the discount that must be added to the coupon interest for the year that it is earned.

A market discount bond is any bond bought for less than par value in the secondary market except:

Market Discount = Par Value – Purchase Price

The market discount is treated as interest, which can be reported annually as accrued interest over the term of the bond or it can be reported as a lump sum when the bond is sold or redeemed. The taxpayer must elect to report the market discount interest annually and the election will apply to all bond purchases made by the taxpayer thereafter. The taxpayer can only change the election with the consent of the IRS. If the market discount is reported as a lump sum, then that portion of the repayment of principal is treated as ordinary interest. The market discount interest that must be reported either as a lump sum or when the issuer pays some of the principal is limited by the market discount.

If a market discount bond also has OID, then the market discount is calculated thus:

Market Discount = Purchase Price – Issue Price – Accrued OID

An OID bond can also be considered a market discount bond if the bondholder's basis is less than the issue price or the bond was issued as a market discount bond because of a reorganization. If the bondholder sells the bond before maturity, then the sale must be reported on Form 8949, Sales and Other Dispositions of Capital Assets.

Examples: Calculating the Original Issue Discount and the Market Discount of a Bond

A corporation issues an OID bond for $800 that pays $1000 upon maturity. However, because demand for the bond was less than anticipated, you pay only $700 to the issuer for the bond. Therefore, $200 of the discount is treated as OID and the remaining $100 of the discount is treated as a market discount. Both discounts are treated as interest, so if you hold the bond until maturity, you have no capital gain.

Case 1: Instead of buying from the issuer, you bought it in the secondary marketplace for $700. The original term of the bond is 10 years, and you bought it 2 years after the issue date; 4 years later you sell it for $900. Therefore:

Accrued Market Discount

There are 2 methods for determining the accrued market discount:

  1. ratable accrual method
  2. constant yield method

Ratable Accrual Method

The ratable accrual method simply divides the market discount by the number of days between the maturity date and the purchase date multiplied by the number of days that the bond was actually held.

Ratable Accrual Method
Accrued Market Discount =Market Discount
(Maturity Date – Purchase Date) in Days
×Number of Days Actually Held

Constant Yield Method

The constant yield method must be chosen by attaching a statement to a timely filed return identifying the bond to which the constant yield method will be applied and cannot be changed for that bond. A constant interest rate can be used to calculate the accrued market discount. The constant yield method, presented in the OID section, is the same method applied to OID bonds. See Publication 1212, Guide to Original Issue Discount Instruments for more info.

De Minimis Imputed Interest is Not Treated as Interest

The interest can be treated as zero if the discount is less than the de minimus value:

De Minimus OID = 0.0025 × Redemption Value × Number of Years from Issue to Maturity

De Minimus Market Discount Interest = 0.0025 × Redemption Value × Number of Years from Purchase Date to Maturity

The de minimus value will, however, have to be reported as a capital gain if held to maturity.

Example — Calculating the De Minimis OID

The de minimus OID for a 10-year bond with a face value of $1,000 = 0.0025 × 1,000 × 10 = $25. If the OID interest is less than $25, then it does not have to be reported as interest, but it must be reported as a capital gain at maturity.

Amortization of Bond Premiums

A bond with a higher coupon rate than prevailing rates will sell for a higher price than par value, so a bond buyer will pay a premium for the bond for its higher interest rate. The paid premium can be amortized over the remaining life of the bond, allowing the bondholder to deduct the amortized amount from the annual taxable interest earned. The annual amortized premium is calculated using the constant yield method for all bonds issued after September 27, 1985. If the premium is not amortized, then a capital loss will be recognized when the bond is redeemed.

Example — Amortizing a Bond Premium

You pay $1100 for a bond with a face value of $1000 maturing in 10 years that pays a coupon rate of 6%. The bond premium = $1100$1000 = $100. Therefore, each year, you can deduct $100/10 = $10 from the $60 received as interest, so you are taxed on $50 of income.

Generally, it will almost always be more advantageous to deduct the amortized premium from the interest income reported annually. Any excess premium that cannot be deducted can be claimed as a miscellaneous deduction not subject to the 2% floor on Schedule A, Itemized Deductions, but the deduction is not available if the standard deduction is claimed. However, the deduction cannot be greater than the total interest on the bonds minus the total premium deductions taken in prior years. If the taxpayer elects to amortize the premium for one bond, then that same choice must apply to all similar bonds acquired thereafter. This election can only be revoked with IRS permission. The election to amortize bond premiums can be made at any time, but the amortized amount of previous years will be added to the cost basis of the bonds. Amortized premiums are deducted from the total interest on Schedule B, Interest and Ordinary Dividends. The amortized premium should be labeled “ABP Adjustment”.

If the bond is a tax-free bond, the premium must be amortized, but no deduction is allowed since the interest is not taxable. The amortization is still necessary to reduce the bondholder's tax basis in the tax-free bond to determine if there is a capital gain upon disposition. The amortized premium also reduces the amount of interest that must be reported, although this does not save on taxes.

Capital Gains or Losses

The capital gain or loss of a bond with imputed interest is determined by subtracting both the purchase price and the imputed interest from the sale price. The imputed interest must be subtracted because it is implicit in the bond's price and accrues over time; the interest from a coupon bond does not have to be subtracted because the interest is paid separately.

Because a market discount is treated as interest, it accrues over time even if the taxpayer elects to pay the tax on the interest when the bond is redeemed or sold, in which case, the accrued imputed market discount interest must be subtracted, along with any accrued OID interest, from the sale or redemption price to calculate capital gain or loss.

Note that if the bondholder holds a discounted bond until maturity, then the redemption price minus the purchase price is treated as interest, and there is no capital gain even though the bond was bought at a discount. Hence, we can summarize the capital gain or loss of a bond by the following equation:

Capital Gain or Loss = Sale or Redemption Price – Purchase Price – Accrued OID Interest – Accrued Market Discount Interest

Example — Calculating the Capital Gain or Loss of a Bond

You buy a bond with a par value of $1000 for $800 that matures in 10 years.

Case 1: you hold the bond until maturity. Therefore, the $200 of discount is treated as interest, for which you must pay ordinary income tax. It does not matter if the discount is OID or a market discount or a combination of the 2. There is no capital gain.

Case 2: you sell the bond after holding it for 5 years for $950. Therefore, since you held the bond for 50% of its remaining term, 50%, or $100, of the discount is treated as interest, and the remaining $50 is a long-term capital gain.

Case 3: same as Case 2, except that you sell the bond for $850. Because your adjusted basis in the bond is the $800 purchase price + $100 of accrued market discount interest, you have a long-term loss of $50.

Tax Treatment of Accrued Interest

When a coupon bond is purchased in the secondary market between interest payment dates, then the sale price includes accrued interest, which is the interest earned by the bond that has not been paid. The accrued interest of the purchased bond is treated as a return of capital, so the buyer of the bond can subtract the accrued interest from the interest reported on Form 1099-INT. The buyer's adjusted basis in the bond is reduced by the same amount, so when the bond is disposed of, the subtracted accrued interest becomes part of the capital gain. When a bond with accrued interest is sold, then the seller must report that part of the sales proceeds attributable to the accrued interest as ordinary interest income.

Example of Tax Treatment of Accrued Interest to Both Buyer and Seller

Joe purchases a bond with a par value of $1,000 that pays $50 semiannually (10% annually), then sells it to Sally before receiving the first interest payment.