Payback Period Method · Payback
Payback Period
What is the payback period?
- The time it takes to recover an investment
- Simple, and shows cash risk clearly
- Ignores returns after payback and the time value of money
What the payback period method really changes is the language of investment discussions. The vague question 'Is this a good investment?' becomes a question of time: 'How many months will our money be tied up?' So it is not only finance staff but also the CEO, who knows the cash position, and line managers who end up discussing it at the same table. The key is that the basis for the decision shifts from profitability to cash turnover, and getting the entire approval chain to see the same picture in a single number is why this method has endured.
There are two ways to calculate it. If cash flow is the same every year, you simply divide the investment by the annual inflow. Real cash flow is uneven, though, so the cumulative method is used: find the year in which cumulative inflows exceed the investment, then divide the remaining amount by that year’s inflow to convert it into months. If you invest KRW 300 million (≈ US$224,500) and receive KRW 80 million (≈ US$59,900) in year KRW 1, (≈ US$1) 120 million in year 2, and KRW 150 million (≈ US$112,200) in year 3, payback is 2.67 years. Apply a 10% discount rate to the same flow and the investment is still not recovered after 3 years. Many companies follow the convention of 2–3 years for IT and systems, 4–5 years for production equipment as the threshold.
Payback period is a risk and liquidity metric, not a profitability metric. NPV tells you how much company value grows and IRR tells you the percentage return, but payback answers only one question: 'How long are we exposed to risk?' So the three should not be treated as either-or choices; put them side by side on one page. A two-gate approach works well: hold the project if NPV is positive but payback exceeds the threshold, and reject it if payback is fast but NPV is negative.
The most common mistake is calculating payback from net income. Depreciation involves no cash outflow, so it must be added back to get a cash view. If you use income statement figures as they are, payback comes out 1–2 years too long and perfectly sound equipment investments get rejected. Conversely, if you count only the savings and leave out maintenance, licensing, and retraining costs, a payback of 2 years becomes 4. Setting the threshold as short as possible is also risky. Quite a few companies have written payback within 2 years into policy, kept rejecting a new line that takes 5 years to pay back but earns for 10, and handed that volume to competitors a few years later.
Okgum LeeExpert in company analysis, investment attraction, and business planning
Eunpyo HongExpert in company analysis, startups, and startup fundraisingThe oldest capital budgeting technique, it was standard practice in industry long before sophisticated discounting methods became widespread.
Consider a hypothetical case. Company A, a food-packaging manufacturer with 90 employees and KRW 24 billion (≈ US$17,956,000) in annual revenue, saw night-shift labor costs rise every year because of a manual inspection process. A proposal for a KRW 280 million (≈ US$209,500) automated inspection machine came up, but the CEO put off approval, saying 'We have not even earned back the line we bought last year.' The production management team spent three weeks recalculating the payback period.
- Manager Kim in production management added KRW 40 million (≈ US$29,900) for electrical work, commissioning and operator training to the KRW 240 million (≈ US$179,600) machine itself, setting total investment at KRW 280 (≈ US$1) million, including items that were missing from the quote.
- The benefit was set at KRW 130 million (≈ US$97,300) a year: KRW 110 million (≈ US$82,300) from moving 3 of the 4 night-shift inspectors to day shifts, plus KRW 20 million (≈ US$15,000) from fewer defect-escape claims.
- When Manager Lee in finance asked, 'Where did the KRW 18 million (≈ US$13,500) in consumables and annual maintenance go?', the net benefit dropped to KRW 112 million (≈ US$83,800) a year, and the payback period slipped from 2.2 years to 2.5 years.
- The CEO’s threshold was 3 years. Manager Kim put a discounted payback of 2.9 years (at an 8% discount rate) and an NPV of KRW 210 million (≈ US$157,100) over a 7-year useful life side by side on one page, and the project was approved on the spot.
- At month 14 after adoption, actual cumulative savings were KRW 134 (≈ US$1) million, about 103% of plan, and Company A then required payback period, discounted payback period, and NPV to be listed together in every investment proposal.