How to Calculate Bond YTM on a BA II Plus (Step by Step)

In this tutorial

• What YTM actually is, in one sentence
• Method 1: solve YTM with the TVM keys (coupon bond)
• Method 2: zero-coupon bond YTM
• Method 3: the Bond worksheet YLD key with real dates
• Semi-annual convention and annualizing the answer
• Common mistakes and error traps

What YTM is (and is not)

YTM is the internal rate of return of a bond's cash flows if you hold it to maturity and reinvest each coupon at the same rate. It is quoted as an annual percentage, but the calculator always solves per period first. For a bond that pays coupons twice a year, every I/Y you compute is a semi-annual rate; the annual YTM is that rate doubled under the bond equivalent yield (BEY) convention.

Before you start, follow the standard setup from the BA II Plus basics tutorial: set decimals to 4 or 9, AOS mode, and P/Y to 1 so you control the period count yourself.

Method 1: Coupon bond YTM with the TVM keys

Think of the bond as a loan from the bondholder to the issuer: you pay the price now (PV), receive a fixed coupon each period (PMT), and get the face value back at maturity (FV). Then solve for I/Y.

Example 1: a 10-year, 8% semi-annual coupon bond priced at 95

A $1,000 par bond pays 8% a year in two coupons of $40, matures in 10 years, and trades at 95% of par ($950). What is its YTM?

1. Clear the TVM registers: press [2nd] then [CLR TVM].
2. Enter the number of coupon periods: type 20 (10 years × 2), press [N].
3. Enter the price as a cash outflow: type 950, press [+/-], then [PV].
4. Enter the semi-annual coupon: type 40, press [PMT].
5. Enter the face value at maturity: type 1000, press [FV].
6. Compute the per-period rate: press [CPT] then [I/Y].

The display reads 4.369 — that is 4.369% per half-year. Double it for the annual bond equivalent yield: YTM ≈ 8.74%. If your calculator returns Error 5, the sign convention is wrong; re-check that PV was entered negative.

Why you must enter PV as a negative number

The TVM keys treat every entry as a cash flow. You hand over $950 (outflow, negative), and you receive coupons plus face value (inflows, positive). If both sides are positive the calculator cannot find a rate and throws Error 5 — the same error you see in NPV problems, explained with every other code in the BA II Plus reset and error guide.

Method 2: Zero-coupon bond YTM

A zero-coupon bond has no PMT. The whole return comes from buying below par and collecting face value at maturity.

Example 2: a 5-year zero priced at 62.10

A $1,000 zero-coupon bond matures in 5 years and is priced at $620.99 (62.10% of par). Find its YTM.

1. Press [2nd] then [CLR TVM].
2. Enter 10 (5 years × 2 semi-annual periods), press [N].
3. Enter 620.99, press [+/-], then [PV].
4. Leave [PMT] at 0.
5. Enter 1000, press [FV].
6. Press [CPT] then [I/Y].

The display reads 4.877 per half-year, so the annual BEY is YTM ≈ 9.75%. Quick sanity check: $620.99 growing at 4.877% for 10 periods should reach $1,000 — yes, 620.99 × 1.0487710 ≈ 1000.

Method 3: The Bond worksheet YLD key

When a problem gives you actual settlement and maturity dates, the Bond worksheet handles day counts for you and returns the YTM as an annual BEY directly. It is the same worksheet used for pricing in the advanced functions tutorial — here you use it in reverse.

1. Press [2nd] then [BOND] (above the number 6).
2. Press [2nd] then [CLR WORK] to clear the worksheet.
3. At SDT, enter the settlement date in the MM.DDYY format, e.g. 10.1525 for October 15, 2025, then press [ENTER].
4. Scroll down to CPN, enter the annual coupon rate as a percentage — 8 for 8% — press [ENTER].
5. Scroll to RV, enter the redemption value per 100 — 100 — press [ENTER].
6. Scroll to ACT and press [2nd] then [SET] if needed to toggle to 2/Y for semi-annual coupons.
7. Scroll to PRI, enter the price per 100 — 95 — press [ENTER].
8. Scroll to YLD and press [CPT].

The YLD line displays the annual yield to maturity, about 8.74% for the same bond as Example 1 — the worksheet just did the date math. Note the settlement date must fall before the maturity date; enter the maturity date at the MAT field on the way down (scroll past CPN to MAT first).

Annualizing: BEY vs effective annual yield

Doubling the semi-annual rate (BEY) is the convention used for quoted bond yields. If a problem asks for the effective annual yield instead, convert the per-period rate: (1 + r)2 − 1. For Example 1: 1.043692 − 1 ≈ 8.93%. Both answers are "the YTM"; the exam tells you which one it wants, and the calculator gives you the per-period rate so you can build either.

Common mistakes and error traps

• Wrong sign on PV. Price must be negative. Symptom: Error 5 or a nonsensical rate.
• Wrong period count. Use coupon periods, not years: 10 years semi-annual = 20 N, not 10.
• Forgetting P/Y = 1. A stray P/Y = 12 divides your rate by 12 and destroys the answer.
• Misreading the result. The I/Y you compute is per period; annualize before comparing to quoted yields.
• Bond worksheet dates. SDT must be before MAT, and the day-count toggle (ACT vs 360) changes the answer slightly — match the problem's convention.

Related tutorials

Bond yields and loan schedules share the same TVM engine. Next, see how every coupon payment splits into principal and interest in the amortization schedule tutorial, use the Date worksheet for maturity and settlement math, and if the answer looks wrong, run down every error code in the reset and errors guide. When you are comfortable with YTM, review the full basics and advanced functions tutorials.

References

• Texas Instruments — BA II PLUS Guidebook (official user manual)
• Texas Instruments — BA II PLUS PROFESSIONAL Calculator Guide
• Eastern Illinois University — Using the Texas Instruments BAII Plus
• AEA — How to Use a BA II Plus Financial Calculator
• BAIIPlus.com — How to Calculate Bond Values Using Bond Mode