What it means
Every piece of durable equipment eventually needs filters, belts, seals, blades, bearings or software updates, and the market that supplies them is the aftermarket. It exists alongside the original equipment market, which covers the first sale of the whole product.
The two markets have completely different economics, customers and buying rhythms even though they involve the same physical machines. The commercial appeal is straightforward: aftermarket parts typically carry gross margins two to four times higher than the original equipment.
Buyers are less price-sensitive because a stopped machine is expensive, availability matters more than a small price difference, and switching to an alternative supplier carries perceived warranty and reliability risk. That combination supports pricing power that the original sale rarely enjoys.
Revenue from parts is also far steadier than equipment revenue. Capital purchases collapse in a downturn while maintenance spending continues, because customers who cannot afford new machines must keep the old ones running.
Manufacturers with a large installed base therefore use parts income as ballast when new-unit sales fall. The key operating metric is the attach rate or capture rate: the share of a customer's parts spending that flows back to the original manufacturer rather than to independent suppliers.
It is driven by lead times, warranty terms, dealer coverage and price gaps, and small improvements in capture rate translate into large profit swings because the incremental margin is so high. There is a genuine tension to manage.
Aggressive parts pricing raises short-term margin but pushes customers towards independent alternatives and can sour the relationship at the next equipment purchase, which is why sophisticated manufacturers price parts as part of a lifetime customer economics model rather than line by line.
In practice
Real-world examples.
Example
A farm machinery dealer sells a combine harvester for $420,000 at an 8% gross margin, earning $33,600. Over the following decade the same customer buys roughly $95,000 of parts at a 50% margin, producing $47,500 of gross profit. The machine was the entry ticket; the parts were the business.
Example
An independent repair chain stocks both original and aftermarket brake sets. The original set sells for $180 at a cost of $120, a 33.3% margin, while an equivalent aftermarket set sells for $110 at a cost of $58, a 47.3% margin. The workshop earns more on the cheaper part and the customer pays less, which is exactly why independent aftermarket suppliers keep winning share.
Example
An industrial pump maker turns over $50,000,000, of which $15,000,000, or 30%, is parts and service. Because that segment carries far higher margins, it contributes well over half the group's gross profit, and the investor presentation leads with installed base growth rather than unit sales.
Formula
Calculation
Aftermarket gross margin = (Parts revenue - Parts cost of goods sold) / Parts revenue
Worked example: an equipment manufacturer reports two revenue streams for the year.
Aftermarket parts: revenue $1,200,000, cost of goods sold $540,000, so gross profit is $1,200,000 - $540,000 = $660,000 and the margin is $660,000 / $1,200,000 = 55%.
New equipment: revenue $9,000,000, cost of goods sold $7,650,000, so gross profit is $9,000,000 - $7,650,000 = $1,350,000 and the margin is $1,350,000 / $9,000,000 = 15%.
Combined: revenue $10,200,000 and gross profit $2,010,000, a blended margin of $2,010,000 / $10,200,000 = 19.7%.
The revealing split is this: parts make up only $1,200,000 / $10,200,000 = 11.8% of revenue but $660,000 / $2,010,000 = 32.8% of gross profit. A third of the company's gross profit comes from an eighth of its revenue.Case study
Seen in the real world.
Calder Press Systems is a fictional printing equipment manufacturer created for this illustrative case study. It sold roughly 40 presses a year at $250,000 each, giving $10,000,000 of equipment revenue at a 14% gross margin, or $1,400,000 of gross profit, and the sales team was rewarded almost entirely on unit volume.
Its installed base had quietly grown to 480 presses, each consuming an average of $9,000 of parts a year. That produced $4,320,000 of parts revenue at a 52% margin, or $2,246,400 of gross profit, comfortably more than the entire new-press business generated, yet parts had no dedicated management and a three-week average lead time.
In this illustrative example the company put a small team on the aftermarket, stocked fast-moving items regionally and cut lead times to two days. Average annual parts spend per press rose from $9,000 to $10,500, adding $720,000 of revenue and $374,400 of gross profit, all from customers it already had and machines it had already sold.
Watch out
Common mistakes.
- Treating parts as a low-status service function rather than a profit centre, so it receives no dedicated management, pricing analysis or inventory investment.
- Assuming aftermarket automatically means lower quality, when many aftermarket suppliers manufacture to the same specification as the original part and some improve on it.
- Setting parts prices purely on a fixed mark-up over cost, which ignores the very different willingness to pay for a machine-stopping component versus a routine consumable.
Questions
People also ask.
What is the difference between aftermarket and original equipment parts?
Original equipment parts come from the manufacturer that supplied the machine, while aftermarket parts may come from that manufacturer or from an independent producer of compatible components.
Does fitting aftermarket parts void a warranty?
Usually not by itself in most markets, though a manufacturer may decline a claim if it can show the non-original part caused the failure.
Why do investors value parts revenue so highly?
Because it is recurring, higher margin and far less cyclical than equipment sales, so it is often valued on a higher multiple than the rest of the business.
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