# Pressure canner vs water bath canner

Source: https://freezeandseal.com/blog/pressure-canner-vs-water-bath-canner
Published: 2026-10-09
Publisher: Freeze & Seal

**Short answer:** A water bath canner surrounds jars with boiling water, which tops out at about 212 F at sea level and is safe only for high acid foods such as most fruits, jams, pickles and properly acidified tomatoes. A pressure canner traps steam so the inside reaches about 240 F, the temperature USDA and NCHFP require to destroy botulism spores in low acid foods such as vegetables, meat, poultry, seafood and beans. If you want to can low acid foods, you need a pressure canner.

This page is for new home canners deciding whether to buy a water bath canner, a pressure canner or both. We explain the line between high acid and low acid foods, the temperatures each method reaches, why that difference matters for botulism, and how altitude changes each process. The canners named here are the All American 921 and the Presto 01781 and 01784 pressure canners from our catalog, plus Ball's electric water bath canners as examples of the other side. Specs come only from their listings; safety guidance follows USDA and the National Center for Home Food Preservation (NCHFP).

## High acid versus low acid foods

Canning safety starts with acidity. USDA and NCHFP draw the line at **pH 4.6**. Foods at pH 4.6 or below are high acid. Foods above pH 4.6 are low acid.

**High acid foods** include most fruits, jams and jellies, fruit juices, pickles and relishes made with tested vinegar recipes, and tomatoes with added lemon juice or citric acid as the tested recipe directs. **Low acid foods** include all fresh vegetables (other than properly pickled ones), meat, poultry, seafood, beans, soups and stocks, and mixtures that contain any of these. Our [what foods need pressure canning](https://freezeandseal.com/blog/what-foods-need-pressure-canning) page lists common examples.

## Temperatures each method reaches

In a water bath canner, jars sit on a rack under boiling water. Water cannot get hotter than its boiling point at normal pressure, which is about 212 F at sea level and lower at altitude. That is enough to kill molds, yeasts and most bacteria in high acid food, and the acid itself keeps botulism spores from growing.

A pressure canner locks the lid and builds steam pressure. At 10 psi on a weighted gauge at sea level, the inside reaches about 240 F. The spores of Clostridium botulinum survive boiling water but are destroyed at 240 F when held for the tested processing time. In a sealed jar of low acid food, any surviving spores can grow and produce a deadly toxin without obvious signs of spoilage. That is why USDA states that pressure canning is the only safe method for low acid foods.

Note: Never water bath can vegetables, meat, poultry, seafood or beans, and never shorten a tested process. Use current USDA or NCHFP tested recipes, and follow the canner maker's instructions for venting and water depth.

## Pressure canners in our catalog

All three pressure canners below can also be used as a water bath canner for high acid foods, which is why many people buy one pressure canner rather than two pots. The two Presto listings say so directly. For the All American, use it with the lid resting loosely and no pressure, or keep a separate stockpot; check the maker's manual.

| Spec | All American 921 | Presto 01781 | Presto 01784 |
| --- | --- | --- | --- |
| Size | 21.5 qt | 23 qt | 23 qt |
| Jar capacity | About 19 pints or 7 quarts | 26 half-pints, 20 pints, 7 quarts | 26 half-pints, 20 pints, 7 quarts |
| Seal | Metal-to-metal, no gasket | Not stated in the listing | Not stated in the listing |
| Pressure control | Steam gauge plus regulator weight | Dial gauge | Pressure gauge, air vent/cover lock |
| Stoves | Gas, electric or flat top | Regular and smooth-top ranges | Induction, gas, electric and smooth-top |
| Water bath use | Not stated in the listing | Yes, doubles as boiling water canner | Yes, doubles as boiling water canner |
| Listed price at writing | $499.95 | $184.99 | $189.99 |

Listing facts for three stovetop pressure canners

[See the best pressure canners](https://freezeandseal.com/best/best-pressure-canner)

## Water bath canners and electric options

A water bath canner is simply a deep pot with a rack and lid, tall enough to cover jars with at least 1 inch of boiling water. Electric water bath canners such as the Ball freshTECH and Ball EasyCanner sit on the counter and hold the water at temperature for you. Both Ball listings state a 21 quart capacity holding 7 quart jars or 8 pint jars.

These are for high acid foods only. They do not build pressure and cannot reach 240 F, so they are never a substitute for a pressure canner with low acid foods. For a countertop pressure canner, see our [electric vs stovetop pressure canner](https://freezeandseal.com/blog/electric-vs-stovetop-pressure-canner) comparison.

## How altitude changes each method

Water boils at a lower temperature as you go up, so both methods need adjusting. For water bath canning, tested recipes add processing time at higher altitudes. For pressure canning, the time stays the same but the pressure goes up. USDA lists weighted gauges at 10 psi up to 1,000 ft and 15 psi above, and dial gauges stepping from 11 psi up to 15 psi in 2,000 ft bands to 10,000 ft. Use our [pressure by altitude tool](https://freezeandseal.com/tools/usda-altitude-pressure) or the [pressure canner altitude chart](https://freezeandseal.com/blog/pressure-canner-altitude-chart), and always confirm against the recipe's own table.

## Which canner to buy first

Before your first batch, read [how to use a pressure canner](https://freezeandseal.com/blog/how-to-use-a-pressure-canner) and [how much water goes in a pressure canner](https://freezeandseal.com/blog/how-much-water-in-a-pressure-canner). If you own a dial gauge model, plan on [testing the gauge](https://freezeandseal.com/blog/pressure-canner-gauge-testing) each season.

- Only jams, jellies, fruit and pickles: a water bath canner is enough.
- Vegetables, beans, stock, meat or soups: you need a pressure canner.
- Both: buy a pressure canner that doubles as a water bath canner, such as the Presto 01781 or 01784.
- Glass top or induction cooktop: check compatibility first; see [best pressure canners for glass top stoves](https://freezeandseal.com/best/best-pressure-canner-for-glass-top-stove).

## Frequently asked questions

**Can I use a pressure canner as a water bath canner?** Many models can, including both Presto canners above according to their listings. Leave the vent open or the weight off so no pressure builds, and cover jars with water as for a normal water bath.

**Can I water bath can tomatoes?** Yes, if you add lemon juice or citric acid exactly as a tested USDA or NCHFP recipe directs. Without added acid, tomatoes can sit too close to the pH 4.6 line.

**Is a pressure cooker the same as a pressure canner?** No. Many small cookers are not designed or tested for canning. See [pressure canner vs pressure cooker](https://freezeandseal.com/blog/pressure-canner-vs-pressure-cooker).

**How long do home canned foods keep?** NCHFP advises using them within about 1 year for best quality, stored cool, dark and dry. See [how long home canned foods last](https://freezeandseal.com/blog/how-long-do-home-canned-foods-last).

## Gear guides for this topic

- https://freezeandseal.com/best/best-pressure-canner
- https://freezeandseal.com/best/best-large-pressure-canner
- https://freezeandseal.com/best/best-pressure-canner-for-glass-top-stove

## Sources

- [National Center for Home Food Preservation](https://nchfp.uga.edu/)