What is purchase price variance (PPV)? Formula, example and how to reduce it
Purchase price variance is the difference between what you paid for a material and the standard price you planned to pay, multiplied by the quantity. This guide gives the formula, a worked example with copper, what makes the number move, and how to manage it when the material is priced off a market.
Purchase price variance in one paragraph
Purchase price variance (PPV) measures how far the price you actually paid for a purchased material is from the standard price set in your budget or standard cost. It is calculated on every purchase, usually reported monthly, and it tells finance whether purchasing is landing above or below plan. A positive PPV means you paid more than the standard, which is called an unfavorable variance. A negative PPV means you paid less, a favorable variance. Some ERP systems and reports show the opposite sign, so check your own convention before comparing numbers.
The PPV formula
PPV = (Actual price − Standard price) × Actual quantity
| Term | What it is |
|---|---|
| Actual price | The price per unit on the purchase order or invoice. |
| Standard price | The planned price per unit, set by finance or cost accounting in the budget and held in the item master. Often fixed for a year. |
| Actual quantity | The units purchased. Some companies use units received; follow your own policy. |
To compare purchases of different sizes, express it as a percentage: PPV % = (Actual price − Standard price) ÷ Standard price. In a spreadsheet, with actual price in column B, standard price in column C and quantity in column D, the formula is =(B2-C2)*D2.
Worked example: buying copper cathode
These figures are illustrative, not market prices. The standard price for copper cathode in the budget is $9,500 per tonne. During the year the team buys 120 tonnes at $10,300 per tonne.
| Per tonne | 120 tonnes | |
|---|---|---|
| Standard price | $9,500 | $1,140,000 |
| Actual price paid | $10,300 | $1,236,000 |
| PPV | +$800 (+8.4%) | $96,000 unfavorable |
PPV = ($10,300 − $9,500) × 120 = $96,000. Had the same 120 tonnes cost $9,100 per tonne, the result would be ($9,100 − $9,500) × 120 = −$48,000, a favorable variance of $48,000.
Favorable vs unfavorable PPV
| Actual vs standard | Sign | Meaning | |
|---|---|---|---|
| Unfavorable | Actual price above standard | Positive | The purchase cost more than planned. |
| Favorable | Actual price below standard | Negative | The purchase cost less than planned. |
A favorable variance is not automatically good news. It can come from a lower-grade material, a longer payment term traded for a lower price, or a standard that was set too high. An unfavorable one is not automatically a purchasing failure either, which is the point of the metals section below.
What causes purchase price variance
- Market price movements. For commodities, the benchmark moves between the date the standard was set and the date of purchase.
- Supplier terms and negotiation. Discounts, rebates, payment terms and contract changes.
- Currency. A purchase priced in another currency than the standard.
- Freight, duties and premiums. Delivery cost and regional premiums that were not in the standard.
- Order size and urgency. Quantity breaks, expedited orders and spot buys at short notice.
- Specification or mix changes. A different grade, alloy or supplier from the one the standard assumed.
- A stale standard. A standard set once a year drifts away from the market, and every purchase inherits the gap.
PPV and the other material variances
Purchase price variance is also called material price variance, or just price variance. It is separate from the material usage (quantity) variance, which compares how much material was used with how much the standard allowed: usage variance = (actual quantity used − standard quantity allowed) × standard price. Many companies calculate the price variance at purchase, so inventory is carried at standard, and the usage variance when the material is consumed.
PPV for metals: why the number is mostly the market
Copper, aluminium, nickel and the other base metals are priced off exchange benchmarks such as the LME. The standard is typically set once, in the budget, from the benchmark at that time plus a premium. Every purchase afterwards is priced off the benchmark of the day. So most of a metals PPV is the benchmark moving, which is why it is so often written off with the reason code "the market moved".
That explanation is usually right and often only partly right. Using the copper example, suppose the standard of $9,500 was built from an LME price of $9,200 plus a $300 premium. Over the budget period the average LME price rose to $9,850, and the order was placed on a day the price was $10,000, with the premium unchanged.
| Part of the $800 per tonne | Per tonne | 120 tonnes |
|---|---|---|
| Market move: benchmark from $9,200 to the period average of $9,850 | +$650 | $78,000 |
| Timing: bought at $10,000 against the $9,850 period average | +$150 | $18,000 |
| Premium: unchanged | $0 | $0 |
| Total PPV | +$800 | $96,000 |
The market move is outside the buyer's control. The timing slice is the part a decision could have changed. We go through how to separate them in purchase price variance on metals: why “the market moved” isn't the whole story.
How to reduce and manage PPV on metals
- Set the standard from a benchmark plus a premium, and refresh it on a schedule. A quarterly refresh keeps the variance about execution and not about a year-old assumption.
- Split the variance by cause. Reason codes for market, timing, premium, currency and other let buyers be judged on what they could influence.
- Price contracts off an index. A formula such as the LME price plus a fixed premium makes the variance traceable to the benchmark.
- Cover part of the volume. Forward buys and hedges fix a price for a share of the volume, which narrows the PPV on that share.
- Time orders with odds, not a feeling. Knowing how likely a 2%, 5% or 10% move is over the next one or three months turns the timing slice into a decision you can defend. See order timing for metal buyers, and the probabilities for copper and aluminium.
Some PPV from market movement cannot be avoided, and a probability is not a guarantee. MetalAlert is decision support, not investment advice; see the disclosures.
Pitfalls when PPV is a KPI
- Gaming. Buying early to lock a favorable variance can build inventory the business does not need.
- A stale standard. Rewarding favorable PPV against a standard set in a different market rewards luck.
- PPV is not savings. It compares with a plan, not with what the market would have charged on the day, so report it next to a market benchmark.
Purchase price variance: common questions
What is purchase price variance (PPV)?
Purchase price variance is the difference between the price you actually paid for a material and the standard price you planned to pay, multiplied by the quantity purchased. Positive means you paid more than the standard (unfavorable); negative means you paid less (favorable).
What is the PPV formula?
PPV = (actual price minus standard price) times actual quantity purchased. As a percentage, PPV % = (actual price minus standard price) divided by standard price.
What is the difference between favorable and unfavorable PPV?
A favorable variance means the actual price was below the standard, so the purchase cost less than planned. An unfavorable variance means the actual price was above the standard. Sign conventions differ between companies and ERP systems, so check how your own reports show it.
What is a good PPV?
There is no universal good number. A PPV close to zero against a standard that reflects the market is a sign the plan was realistic. A large favorable variance that keeps recurring usually means the standard is stale, not that purchasing is outperforming. For metals, judge the part buyers can control separately from the part that is just the market moving.
Is purchase price variance the same as material price variance?
In most companies, yes. Purchase price variance, material price variance and price variance usually refer to the same calculation on purchased materials. It is different from the material usage (quantity) variance, which compares how much material was used with how much the standard allowed.
How do you calculate PPV in Excel?
Put the actual price in one column, the standard price in a second and the quantity in a third, then use =(actual price - standard price) * quantity, for example =(B2-C2)*D2. A positive result is unfavorable and a negative result is favorable. Sum the column for the total PPV of a period.
What causes purchase price variance on metals?
Mostly the benchmark price moving between the date the standard was set and the date of purchase, since metals such as copper and aluminium are priced off exchange benchmarks. The rest comes from where within the period the order was placed, changes in regional premiums, currency, freight, order size and supplier terms.
How can you reduce PPV on commodity metals?
Set standards from a benchmark plus premium and refresh them on a schedule, split the variance into market, timing and other causes, use index-linked pricing so the number is traceable, cover part of the volume with forward buys or hedges, and decide order timing with a probability of a price move instead of a feeling. Some PPV from market movement is unavoidable.
See the odds behind your timing decisions
MetalAlert estimates the probability of a 2%, 5% or 10% move in each LME base metal over one and three months, with alerts at the level you choose. Book a short walkthrough and we will show it against your own purchases.