Can I use pasta sauce or mayonnaise jars for home canning?

No. Commercial food jars use thinner glass, have a sealing rim not designed for a standard two-piece flat lid, and break at higher rates under repeated thermal cycling. They are especially unsuitable for pressure processing. Keep them for dry goods storage or refrigerator pickles.

Do reusable plastic canning lids actually work?

They do seal when the manufacturer's method is followed, and at roughly $0.88 a set against $0.28 for disposables they pay for themselves around the fourth cycle. NCHFP has not conducted its own trials on these closures, so the available evidence is manufacturer data rather than extension testing.

How can I tell if a used canning jar is still good?

Run a fingertip around the sealing rim and hold the jar up to a light. Any chip you can feel, any hairline crack in the wall or base, and any cloudy mineral scale that will not scrub off the sealing surface retires the jar to dry storage rather than the canner.

Canning Jars: Sizes, Lids, Reuse Rules, and Cost Per Jar

Q: Can I reuse canning lids?

Not the flat metal ones. The sealing compound on the underside compresses permanently during the first process, and USDA and NCHFP guidance treats flat lids as single-use items. The screw bands and the jars themselves are reusable for many years, as long as the bands are free of rust and the jar rims are free of chips.

Q: What is the difference between regular mouth and wide mouth canning jars?

Thread diameter: regular mouth is 70 mm and wide mouth is 86 mm, and lids are not interchangeable between them. Wide mouth jars are easier to pack with whole tomatoes or pickle spears and easier to clean; regular mouth jars and their lids cost slightly less per unit.

Q: Are half-gallon jars safe for canning?

Only for apple juice and grape juice, which is the one tested boiling-water process published at the 64 oz size. Everything else lacks validated heat-penetration data in a half-gallon jar, because heat reaches the center of a wide, tall column of food too slowly to rely on a scaled-up time.

Updated August 2026 · Editorial team · Topic: canning / food safety

Canning Jars: Sizes, Lids, Reuse Rules, and Cost Per Jar — Canning

A dozen quart jars runs $15.50 at a farm store; the flat lids on top cost another $3.30 a box. Those two numbers behave nothing alike — the glass survives twenty seasons, the lid is built to seal exactly once. Most beginner spending goes to the wrong half of that pair. Size carries a safety load too: a tested process time belongs to one jar volume and does not transfer upward.

Short answer: Standard Mason jars come in 4, 8, 12, 16, 24, 32 and 64 oz, in two thread widths — regular mouth (70 mm) and wide mouth (86 mm). Glass costs $0.95–$1.55 a jar in 12-packs and lasts decades; the closure splits into a single-use flat lid at $0.22–$0.35 and a reusable band. Over ten seasons a filled quart carries about $0.41 in container cost. Reusable polymer lids run $0.85–$0.90 a set and break even near the fourth cycle. Half-gallon jars have a USDA-tested process only for apple and grape juice.

Reviewed by the BackyardStead Lab editorial team. We publish real ROI, plain numbers and USDA/extension data so you can judge for yourself — we run the math, not a farm. Educational information only: backyard-chicken and livestock rules vary by city, home canning must follow USDA/NCHFP-tested methods (botulism risk), and mushrooms should be grown only from a known-species kit — never foraged on our word.

The seven sizes, and which ones have tested processes

Two thread standards cover nearly every jar sold in the US, and they do not cross: a 70 mm lid will not seal an 86 mm rim. Wide mouth takes whole tomatoes and spears without bruising; regular mouth costs a bit less. Volumes are fixed across brands, so a pint takes the same process time whoever made it.

Size	Volume	Mouth	Typical contents	Per canner load
Quarter-pint	4 oz	Regular	Jelly, hot sauce	12–24, double stacked
Half-pint	8 oz	Both	Jam, chutney, relish	16–18, double stacked
Three-quarter pint	12 oz	Regular	Jam, syrups	12–14
Pint	16 oz	Both	Salsa, vegetables, meat	9
Pint-and-a-half	24 oz	Wide	Spears, dry storage	7, few tested processes
Quart	32 oz	Both	Tomatoes, beans, broth	7
Half-gallon	64 oz	Wide	Apple and grape juice	4, no other tested process

The last two rows matter most. Heat crosses a wide column of food slowly, and process times were validated jar by jar in laboratory trials, not scaled from volume. The National Center for Home Food Preservation publishes a boiling-water process for half-gallons of apple and grape juice and nothing else at that size. The 24 oz jar sits in the same gap.

Acidity sets the method before volume sets the minutes. Anything above pH 4.6 — plain vegetables, meat, poultry, corn — is low-acid and needs a pressure canner whatever jar it fills, because Clostridium botulinum spores shrug off 212°F. That is the line between the methods.

Lids: the part you keep rebuying

A two-piece closure is a flat metal disc carrying a ring of sealing compound, plus a band that holds it until vacuum forms. The compound softens under heat, flows into the texture of the rim, and sets as the jar cools — once. That is why USDA and NCHFP guidance treats flat lids as single-use and the band as reusable.

Closure	Price each	Reusable?	Notes
Flat lid, regular mouth, 12-box	$0.28	No	Default choice
Flat lid, wide mouth, 12-box	$0.35	No	~25% more per unit
Flat lid, bulk 100-pack	$0.22	No	Cheapest above 60 jars/year
Screw band, metal	$0.25	Yes, years	Retire at rust or dent
Polymer lid + gasket set	$0.85–0.90	Gasket wears	Spare gaskets ~$0.25
Plastic storage cap	$0.55	Yes	Refrigerator only, never processed

Reusable polymer lids — Tattler and Harvest Guard are the common brands — swap the bonded compound for a separate gasket. A $0.88 set against $0.28 disposables, allowing $0.05 a cycle for gaskets, crosses over on the fourth use. Technique differs too: band snugged before processing, tightened as the jars leave the canner. NCHFP has not run its own trials on these closures and points users to the maker's directions.

Headspace goes with the contents, not the brand, and ranks second behind reused lids among causes of failed seals.

Contents	Headspace
Jams, jellies	¼ inch
Juices, pickles, most fruit	½ inch
Tomatoes with added acid	½ inch
Vegetables, meat, poultry — pressure only	1 inch

What a jar actually costs to fill

Glass is capital, lids are consumable, so they get separate lines. A 12-pack of regular-mouth quarts at $15.50 is $1.29 apiece. Breakage runs a few percent a season, mostly thermal shock, so ten seasons is conservative and twenty realistic.

Per filled jar	Half-pint	Pint	Quart
Jar, 12-pack price	$1.04	$1.13	$1.29
Jar per season (÷10)	$0.10	$0.11	$0.13
Flat lid, plus band	$0.29	$0.29	$0.29
Container total	$0.39	$0.40	$0.41
Year one, glass included	$1.33	$1.42	$1.58

Year one is why a first season rarely pays for itself: seventy quarts of glass plus lids is about $110 before a single tomato gets bought, near what the canner itself costs. From season two the container line holds at $0.41 a quart, which is what keeps a home jar competitive against a $2.20–2.90 store can. Estate sales price used jars at $0.25–0.75, and any that passes a rim check is as good as new.

Data note: Jar volumes, headspace figures, single-use lid guidance and the half-gallon juice exception come from the USDA Complete Guide to Home Canning and its NCHFP republication at nchfp.uga.edu; the reading on reusable polymer lids is NCHFP's own wording about untested closures. Prices are US retail checks from mid-2026 and move seasonally — lids in particular spiked in 2020. BackyardStead Lab runs the math rather than a cannery, so no jar cupboard here is ours.

Reuse rules, item by item

Jars — indefinitely, inspected every time. Run a fingertip around the sealing surface. A chip you can feel at 1/16 inch gives the compound nothing to grip; cracks in the base fail under heat instead, usually inside the canner.

Flat lids — once. The compound already took the shape of one rim. Bands — until they rust. A band does nothing once the jar cools, which is why storage guidance says to take it off; left on, it can hold an unsealed lid in place and hide spoilage.

Commercial food jars — no. Pasta sauce and mayonnaise jars use thinner glass with a narrower rim, break more under thermal cycling, and their lug finish rejects a flat lid. Vintage zinc-cap and wire-bail jars are display pieces: no way to verify a seal, no tested process.

Common mistakes, in numbers

Reusing flat lids to save $0.28. A quart of home-canned tomatoes holds about $2 of produce and a share of three hours' work — a poor thing to wager on a used disc.
Moving a pint recipe into a quart jar. Times differ by size: green beans take 20 minutes for pints and 25 for quarts at 11 PSI. See the bean times by jar size.
Filling half-gallons with solid food. With no tested process at 64 oz, the center trails the target temperature for the whole run.
Torquing the bands, then storing them on. Fingertip tight is the spec; over-tightened rings trap escaping air and drive siphoning. A year later a corroded band can mask a lid that never sealed.

FAQ

Can I reuse canning lids?

Not the flat metal ones — the compound compresses permanently on the first process. Bands and jars last for years.

What is the difference between regular mouth and wide mouth?

Thread diameter, 70 mm against 86 mm, and lids do not cross between them. Wide mouth packs easier, regular mouth costs less.

Can I use pasta sauce or mayonnaise jars for canning?

No — thinner glass, a rim not built for a flat lid, and a breakage rate that worsens under pressure. Keep them for dry goods.

Are half-gallon jars safe for canning?

Only for apple and grape juice, the one tested process published at that size.

Do reusable plastic lids actually work?

They seal when the maker's method is followed and pay back on the fourth cycle at $0.88 a set. The evidence is manufacturer data, not extension trials.

How can I tell if a used jar is still good?

Fingertip around the rim, then hold it to a light. Any chip, crack, or scale that will not scrub off retires the jar to dry storage.

Related:

Educational information only, not medical or dietary advice. BackyardStead Lab keeps no commercial kitchen or farm; jar sizes, headspace figures and lid guidance here follow USDA and NCHFP published guidance, and any home canning of low-acid food should follow a current tested recipe for your jar size and altitude. Prices and product availability vary by region and season — verify current local numbers before you buy.