We have been trying to price robot depreciation for six weeks and kept failing for the same reason: the used-industrial-robot listing sites either time out, 404 or refuse automated reads, and the ones that answer do not publish hours or install dates. Dairy does. Sellers of used milking boxes state the model, the year it went in, the year it came out and often the hours, because the buyer is a neighbouring farmer who will ask anyway.
So here is the depreciation curve, built from nine US listings live in the past twelve months. It is not a curve.
The table
Retention is measured against $150,000-$200,000 per robot, the figure University of Maryland Extension published for a box rated at 50-70 cows. We use the $175,000 midpoint.
| Machine | Generation | Vintage | Ask per robot | Retention |
|---|---|---|---|---|
| Lely Astronaut A5 ×2, complete system | current | installed Aug 2022, ~85,000-95,000 milkings each | $162,500 | **92.9%** |
| GEA R9500 ×2, new, never installed | current | zero hours | $135,000 | **77.1%** |
| GEA R9500 ×3, full system | current | installed new 2021 | $108,333 | **61.9%** |
| Lely A4 ×2 (net of $20,000 of parts) | transitional | new 2018, ran 15 months | $100,000 | **57.1%** |
| AMS Galaxy 20.20 Astrea ×2, double boxes | current | one running, one needs a wash board | $85,000 | **48.6%** |
| Lely A3 ×4, 700,000 milking hours | retired | Dec 2009 - Sep 2024 | $12,500 | **7.1%** |
| Lely A3 ×4, taken in a lot of four | retired | as above | $10,000 | **5.7%** |
| GEA MonoBox ×18, with control panels | retired | not stated | $10,000 | **5.7%** |
| Lely A3 ×4 + Grazeway gates, package | retired | "working when they stopped" | $9,375 | **5.4%** |
There is nothing between 48.6% and 7.1%. Every machine in this sample is either worth roughly half to all of a new one, or roughly a twentieth. The gap between the cheapest current-generation box and the most expensive retired one is a factor of 6.8; between the A5 and the A3 package it is 17.3×.
The cliff is a parts announcement, not a wear curve
The 700,000-hour A3 listing says why, in the seller's own words: *"We have been advised that Lely will no longer be making parts for this model of robot as of the spring of 2025."* The same listing's pitch is aimed at exactly one kind of buyer — *"If you have Lely A-3 robots, this would be a wonderful way to keep things operating"* — and the other A3 package says its units "could also be purchased to be parted out."
That is the whole mechanism. A milking box does not lose its value by wearing out. It loses its value when the only remaining buyers are people who already own the same discontinued model, a population that only ever shrinks.
Our view: hours are the wrong thing to negotiate over, and the data says so directly. Compare the two A3 lots. One ran 14.7 years and 700,000 milking hours to September 2024 and asks $12,500 a robot. The other was retired healthy — the dairyman simply installed newer models — and asks $9,375. The worn-out set is priced 33.3% above the sound one. Whatever is setting these prices, it is not condition.
Four smaller numbers worth keeping
New, never installed, sells below new. The GEA two-robot package at $135,000 per box has zero hours and current hardware, and still lists 10.0% to 32.5% under the extension band. What the discount buys back is everything that does not come in the crate: the dealer relationship, the financing and the service contract.
Volume moves price by exactly a fifth. The A3 seller drops $12,500 to $10,000 each if you take all four — −20.0%. A completely unrelated seller of refurbished Lely Juno feed pushers drops $15,000 to $12,000 each at four or more — −20.0%. Two sellers, two machine classes, the same break. Treat 20% as the standing volume discount in this market rather than an opening position.
One component can be a third of the machine. The AMS Galaxy listing notes that one of its two robots carries "a brand new motoman (~$60k just by itself)" inside a package asking $170,000. The arm alone is 35.3% of the ask for both boxes. That matches what we found tearing down Universal Robots spare-parts pricing: the manipulator is the machine, and the enclosure is packaging.
A used box is worth what its brand's parts network says it is worth. Peripherals barely move it. The A3 package prices Grazeway gates at $2,000 each and a CRS control with washer at $3,750 — real money, and irrelevant next to a 17-fold swing in the robot itself.
This breaks our own cross-category rule, and that is the finding
Twice this month we concluded that robot spare parts are priced at a premium to the whole machine. On 2 August, three Universal Robots wrist joints came to 44.8-49.9% of a complete UR5e, and a six-joint rebuild exceeded the price of a new UR12e. On 5 August, an EAVision J100 rebuilt from its own dealer's parts catalogue came to $25,813 against a $21,999 new airframe — 17.3% above the machine. We generalised that to "robot spare parts are not a discount on the machine, they are a premium."
Dairy inverts it. A dealer is clearing new-in-box AMS Galaxy Astrea parts — Moto Wrist, attach tool, vision PC, valve boxes, milk pump — with a stated inventory value of $84,000, priced as a lot at $25,000. That is −70.2%, and it is new stock, not salvage.
So the rule needs a condition attached. Parts carry a premium where the installed base is growing and a liquidation discount where it is shrinking. Universal Robots and EAVision are selling machines today, so every spare has a captive buyer at list. A discontinued dairy platform has a fixed and falling number of machines that can ever consume a spare, and the inventory has to clear before the last one is retired. Both halves of that sentence show up in the same market: the A3 robots at $9,375 are being sold *as* parts, while a shelf of parts for a dying platform goes at thirty cents on the dollar.
What to do with it. If you are buying used, the only question that changes the number by an order of magnitude is how long the manufacturer will still make parts — not hours, not cosmetics, not the peripherals in the package. If you are buying new, that same question is the resale value you are quietly purchasing, and it is worth asking a dealer to put in writing how long the model has been in the line. For what these machines cost to buy in the first place, see our robotic milking system price guide, which prices the same machines from the buyer's side.
Sources
- University of Maryland Extension, *Robotic Milking System*, Lexi Urbanz and Fabiana F. Cardoso, 6 December 2023 — https://extension.umd.edu/resource/robotic-milking-system
- Dairy Train Classifieds, robots category and individual listings DTCS-2603, DTCS-2910, DTCS-2918, DTCB-0339 (read 9 August 2026) — https://www.dairytrainclassifieds.com/advert-category/robots/
- Dairy Dealer LLC public catalogue, listings DD2922, DD2910, DD2973, DD2904 (read 9 August 2026) — https://www.dairydealer.com/
- GrabaRobot, *Universal Robots Spare Parts Cost Share 2026* — https://www.grabarobot.com/blog/universal-robots-spare-parts-cost-share-2026/
- GrabaRobot, *Spray Drone Package vs Parts 2026* — https://www.grabarobot.com/blog/spray-drone-package-vs-parts-2026/
Limitations. These are asking prices on a small sample of nine listings, not clearing prices, and asking prices in a thin market run high. Per-robot figures for multi-robot packages are derived by division, which credits the robot with the value of the peripherals bundled beside it. The retention denominator is a December 2023 extension figure, not a 2026 dealer quote; if new prices have risen since, every retention percentage here is too high. The $84,000 parts valuation is the selling dealer's own statement, not a price list we verified line by line. We did not control for left- versus right-hand box configuration or for geography, both of which move resale in this market.
