How to Water-Bath Can (Step by Step)
Water-bath canning submerges filled jars of high-acid food in boiling water for a tested time, sealing them for shelf storage. Use it only for high-acid foods (jams, pickles, acidified tomatoes) and follow tested USDA or NCHFP recipes for times and altitude.
Water-bath canning is the gateway to home canning, simpler than pressure canning and perfect for jams, pickles and fruit. The catch is that it is safe only for high-acid foods.
What you need
- A water-bath canner (or a big pot with a rack)
- Canning jars, new flat lids and bands
- A tested recipe for your food
The process in outline
- Prepare jars and food per your tested recipe.
- Fill jars to the specified headspace; remove air bubbles; wipe rims.
- Submerge jars in boiling water, covered by an inch or more.
- Process for the exact time your recipe gives, adjusted for altitude.
- Cool undisturbed, then check that each lid has sealed.
Where to start
Beginner-friendly first projects include jam and pickles. For jars, see the best water-bath canning kit, and read is home canning safe? first.
- National Center for Home Food Preservation (NCHFP) — tested home-preservation methods and the USDA Complete Guide to Home Canning
- USDA Food Safety and Inspection Service (FSIS)
- U.S. Food & Drug Administration (FDA) — Food
- FoodSafety.gov
Frequently asked questions
What foods can be water-bath canned?
Only high-acid foods: jams and jellies, most fruit, pickles, and properly acidified tomatoes. Low-acid foods (vegetables, meats) require a pressure canner.
How does water-bath canning work?
Filled jars are boiled in a water-bath canner for a tested time. The heat and the food acidity make it safe, and cooling creates the vacuum seal.
Do I adjust water-bath times for altitude?
Yes. Higher altitude requires longer processing. Tested recipes include altitude adjustments, follow them.