Picture two buyers going through the same weekly resin report on a Monday morning. Spot polyethylene is off a penny, polypropylene is flat, and producers are asking for another five cents next month. Neither can tell from that resin price report that one is paying a few cents a pound more than the other for the same grade.
That’s because a report only shows where the market traded and where the monthly index settled. What each buyer pays after its own negotiated discount never shows up in it.
So a report can’t answer the one question those two buyers would most want answered, but it answers plenty of others. Once you know what each line means, you get a pretty clear picture of where prices are heading and whether your supplier’s explanation for the next increase holds up.
Whether they come out weekly or monthly, most plastic resin price reports follow the same basic layout, which longtime buyers know all too well. Below the headline, they usually cover four areas:
Of those four, the contract section is the one that reaches your invoice, so it's the place to start. Most of it turns on two words, nominations and settlements.
A nomination is a producer's notice that it wants to raise contract prices by a set amount on a set date. When a report mentions "a nickel nomination for June," that nickel is the producer's opening ask, and how much of it sticks depends on inventories, demand, and how many buyers push back. That's why a resin price increase nomination tells you more about what a producer wants than about what you'll pay.
The settlement, on the other hand, is where the month's contract price ends up. For polyethylene, price reporting services survey buyers and producers, then publish an assessed price for each benchmark grade and how far it moved. That assessed price is "the index." Most polyethylene contracts are written off it, usually as the index minus a discount you negotiated, so when the index moves, your price moves with it.
Timing can trip you up, too. When a report says June polyethylene settled up two cents, that move applies to June, but the number usually isn't out until early July. Because of that delay, some contracts price this month's shipments off a prior month's index, which the trade calls a lag, while others bill provisionally and adjust once it's out. When a pending increase, one that hasn't settled yet, finally goes through, the service may book it back to the month it was nominated for, and your supplier then adjusts invoices you've already paid. The services don't all handle that the same way, so it helps to know which one your contract names.
Not every nomination settles cleanly, and some of the most telling lines in a report cover the increases that stall, shrink, or slip. Polyethylene increases can sit "pending" for a month or two, sometimes longer. When one goes through only in part, say two cents of a five-cent ask, producers often try for the other three cents the following month. Other increases get rolled over whole to a later month, and some get dropped altogether.
Because producers often ask for more than they expect to get, one partial settlement doesn't tell you much. Track those lines over several months next to inventories, feedstock costs, and supply, though, and you'll get a fair sense of whether producers have pricing power or are mostly passing on higher costs. You'll want that answer before replying to the next increase letter.
All of that is mostly a polyethylene story. Many polypropylene (PP) contracts take the monthly polymer-grade propylene price, or PGP, and add a margin, so propylene moves pass straight through.
Other PP contracts are tied to the published PP index. When that index settles up by more than PGP moved, the extra is usually producer margin, often announced as a separate increase. A contract tied to the index picks that up automatically. On a PGP-plus-margin contract, the increase waits for renewal if the margin is set for the term, but if it's negotiable, expect your supplier to push for it sooner.
The contract lines tell you where your invoice is headed, but they only come out once a month, after that month is already over. Spot resin prices move faster because they reflect what traded that week. For a read on resin prices this week, look at the spot section. Spot often turns first, and contract can hold flat for months while spot falls.
Spot prices are quoted by quality tier, so check which tier a number is for before setting it against your own:
Reports quote those prices for railcar-sized lots, the standard bulk unit. If you buy by the truckload or in bulk boxes, your price usually runs higher and follows the quote more slowly, especially on the way down. The railcars say something about supply, too, since scarce prime cars mean producers have little extra to sell, while heavily discounted ones mean they've got more than they can move.
The published index reflects prices before the discounts most contract buyers get, which is partly why spot polyethylene trades below it in a normal or soft market. In a tight market, spot can run above the index. Since some distance between the two is normal either way, it takes a spot vs contract pricing spread that keeps widening for several weeks to hint at extra material in the market. On its own, though, spot is too small a slice of total volume to prove your supplier will give on contract.
Spot can hint that there's extra resin around, but it can't tell you why prices moved. The supply and feedstock lines explain the move, so they're where to check a supplier who blames an increase on tight supply or higher costs.
Producer inventories show whether resin is piling up or getting drawn down, and since the monthly figures run a few weeks behind, read them next to the report's more current news on outages and turnarounds. North American producers also export a large share of their polyethylene every month, so the number to watch is how much that volume shifts. When exports slow and domestic demand doesn't pick up, the resin that would have shipped tends to pile up here as inventory, which pressures prices.
Most reports also quote operating rates, the share of industry capacity that's running. A high rate sounds like tight supply, but if inventories are climbing too, producers are often making more than they can sell, so on their own, operating rates in the resin market can point you the wrong way.
The feedstock lines answer the cost side of the story. When a supplier says costs pushed an increase but ethane, natural gas, or PGP has barely moved, the cost argument gets a lot weaker, and it's fair to ask what else changed.
So if producers are asking for five more cents while inventories climb, exports slow, and feedstock costs hold steady, you've got a solid start on your counterargument right there in the report.
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That's a lot to get out of one report, and it still leaves the two buyers from Monday morning where they started. Even a careful read won't tell either of them whether their own price is competitive, since that number depends on several things no resin market report ever sees:
And since the published figures are survey-based resin benchmarks, they can trail the market when prices move fast and won't always match what comparable buyers actually pay. That's no reason to stop reading them for direction, as long as you don't expect them to tell you whether you're the buyer paying the extra few cents. Your supplier, after all, knows what it charges every buyer on your grade, and the report doesn't.
So the question the two buyers started with, whether their own price is the high one, needs a number the report doesn't carry. You can get partway there with a simple monthly log, though. Write down each nomination next to what eventually settled, then add your own net contract price and the spot price beside the published index. Keep it going for six months to a year and you'll see how your supplier behaves and how your price tracks the market. Other buyers' prices are the one thing it can't show you, and that's the comparison both buyers needed in the first place.
ResinSmart gives resin buyers market analytics that show how the market and prices on their grades have moved, which covers the market side of that log. To see where your own price sits against comparable buyers, you need benchmarks, and depending on the plan, ResinSmart adds those, informed by more than 3 billion pounds of transaction data, along with advisory support when it's time to negotiate. Start your free trial today and see what your grades have done lately.
A resin price report is a weekly or monthly summary of how plastic resin prices moved, covering spot trading, contract nominations and settlements, feedstock costs, and supply. These reports show market direction for resins like polyethylene and polypropylene, not what any single buyer pays.
When a resin price report says contracts settled, the service behind it has assessed where that month's contract price ended up. The move applies to that contract month, and when it reaches your invoice depends on your contract's terms.
Prime resin in a price report is on-spec material, sold under a producer's brand or as generic prime, while offgrade resin falls well outside spec and trades at a discount. Wide-spec material sits between the two on both spec and price.
Polypropylene prices in a resin price report follow PGP because many polypropylene contracts are priced off the monthly polymer-grade propylene settlement plus a margin that's usually set for the contract term, so they move with PGP. When the published PP index moves by more than PGP, the extra is mostly producer margin, though contracts with a different propylene reference can differ.
Resin price reports usually come out weekly for spot trading, while contract price moves get assessed and reported once a month. The monthly number usually comes out early the following month.
A resin price report can't tell you whether your resin contract price is fair, because it tracks market direction rather than what buyers like you pay. Your price also depends on grade, volume, freight, and your contract discount, so judging fairness takes a benchmark built from comparable buyers' transactions.