Every bottle cap question is really one question: the sorting screens at a recycling plant drop anything smaller than a few inches, so a loose cap of any material is lost before any machine can read it. The answers follow. Metal caps travel pinched inside a like-metal can. Plastic caps stay screwed on the bottle, where a water bath separates them later. And the famous pull tab, subject of a fifty-year charity legend, is real, collectable and worth about a fiftieth of a cent.
Start with the legend, because the arithmetic behind it teaches everything else on this page.
The legend of the pull tab
The story has circulated for decades in several versions: save tabs for dialysis time, save tabs because the tab is purer aluminium than the can, save tabs because they are worth more than the can they open.
Here is what is true. A well-known children’s charity genuinely runs pull tab programmes across its chapters, its recycling partners genuinely weigh the tabs and pay the going aluminium rate, and one chapter reports the tabs raising around $2,500 a year. The programme is real and the money is real.
The arithmetic is where the legend collapses.
- A tab weighs about a third of a gram, roughly 1,000 tabs to the pound by the charity’s own count.
- The tab is the same aluminium value per pound as the can it opens, not a premium grade, and it carries about 2.5 percent of the can’s metal.
- One tab is worth around a fiftieth of a cent. A million tabs, several bin liners full, cash out near $200.
- A whole can is forty tabs’ worth of metal. In a deposit state it is worth 250 to 500 tabs at redemption.
So why do the charities keep the programme, and say so themselves? Because tabs are clean, dry, compact and perfect for engaging children, where sticky whole cans are none of those things. One chapter is candid enough that it now asks collectors to take tabs straight to the partner scrap yard, having run out of space to store them at the house.
Collect tabs happily, then, but as a teaching habit rather than a fundraising strategy. If the aluminium is the point, donate whole cans or redeem deposits and give the cash, which multiplies the same gesture forty to five hundred times.
The rule every cap shares
A sorting plant sizes material on screens within the first seconds, and anything smaller than roughly three inches falls through with the broken glass and grit, exactly as our metal recycling guide shows machine by machine.
A loose cap, metal or plastic, is below that size. Nothing downstream ever sees it. Every correct answer on this page is a way of making a cap travel as part of something bigger.
Metal caps: the pinch trick
Steel crowns from beer bottles, twist-off crowns, and the steel lids from jars are all magnet material; aluminium screw caps from wine and spirits are eddy current material. Both recover perfectly at full size and vanish at cap size.
- Steel caps and crowns: collect them in an empty steel food can, and when it is half full, pinch the opening closed. The magnet lifts the whole package.
- Aluminium screw caps: same trick in an aluminium drinks can, pinched at the top.
- Jar lids wider than a few inches can go loose; smaller ones join the steel can.
- A jam jar of a hundred steel crowns holds about 7.3 cents of steel at today’s board price, which is why this is a sorting habit rather than a payday.
- The same charity chapters that take tabs commonly take metal bottle caps too, under the same weigh-and-redeem arrangement.
Plastic caps: leave them on
The guidance here reversed some years ago, and the reason is a water bath.
At a plastics reclaimer, bottles are ground into flake and washed. PET bottle flake sinks; the polypropylene and polyethylene of the cap float. The two plastics separate themselves, and both are recovered. That separation is why the plastics recycling industry now asks for caps screwed back on, bottle emptied and crushed so the cap does not hold pressure.
A cap taken off and binned loose fails the screen rule instead. On the bottle it rides through sorting at bottle size and separates at the wash. This is the same size logic that puts shredded paper in a bag and small foil in a ball.
Pump heads and trigger sprayers are the exception: they hide a steel spring and mixed plastics, so they go in general waste while the bottle recycles.
Quick answers for the odd ones
- Corks are not caps: natural cork composts or goes to specialist collection, synthetic cork is general waste.
- Champagne cages are steel wire, and wire is a tangler; twist the cage around its own cap into a ball with the foil crown, or bin it.
- Kombucha and swing-top ceramic stoppers stay on the bottle for reuse, or general waste.
- Metal screw caps from glass jars of sauce are steel lids and follow the pinch trick.
- Tabs already detached still recycle; drop them in your aluminium-cap can rather than loose.
Where this fits
Why the screens drop small items, and how the magnet and eddy current recover what survives them, is on can you recycle metal. What a whole can is worth against its tab sits in aluminium can recycling, and the deposit-state comparison that multiplies a can’s value is in recycling plastic bottles for cash.
Frequently asked questions
Are bottle caps recyclable?
Yes, but never loose. Sorting screens drop anything smaller than a few inches within seconds, so a loose cap of any material is lost before the machines see it. Metal caps travel pinched inside a like-metal can, and plastic caps stay screwed on the bottle.
Why do loose caps fail at the recycling plant?
Size. Plants screen material by dimension at the very start of the line, and cap-sized items fall through with broken glass and grit. Nothing downstream, magnet or eddy current, ever gets the chance to recover them.
What is the pinch trick for metal caps?
Collect steel crowns and lids in an empty steel food can, and aluminium screw caps in an aluminium drinks can, then pinch the opening closed when half full. The caps travel at can size, and the magnet or eddy current captures the whole package.
Should plastic caps be left on bottles?
Yes, screwed back on with the bottle emptied and crushed. At the reclaimer, ground PET flake sinks in the wash bath while cap plastic floats, so the two separate themselves and both are recovered. This reversed the older caps-off advice.
Is the pull tab charity programme real?
Entirely real. A well-known children's charity collects tabs across its chapters, recycling partners weigh them and pay the aluminium rate, and one chapter reports around $2,500 a year raised. What is false is the idea that tabs are special metal.
Is a pull tab worth more than the can?
No, and it is not close. The tab is the same aluminium value per pound as the can and carries about 2.5 percent of the can's metal, roughly a fiftieth of a cent each. A whole can is forty tabs of metal, and in a deposit state it redeems for 250 to 500 tabs' worth.
Why do charities collect tabs instead of cans?
Their own stated reasons are practical: tabs are clean, dry, compact and easy for children to collect, where sticky whole cans are none of those things. One chapter now sends collectors straight to its partner scrap yard, having run out of storage space.
What should I do with pump heads and trigger sprayers?
General waste. They hide a steel spring and several plastics that no household stream separates, while the bottle underneath recycles normally with its cap screwed on.
How much are collected bottle caps worth?
Very little, which is fine because sorting is the point. A jam jar of a hundred steel crowns holds a few cents of steel at board prices, and charity cap collections earn by accumulated weight rather than per cap.
What about corks and champagne cages?
Corks are not caps: natural cork composts or goes to specialist collection, synthetic cork is waste. The wire cage is a tangler, so twist it around its own cap and foil into a ball, or bin it.