Altitude adjustment for canning

Water boils cooler as you go up. Above 1,000 feet the numbers in your recipe are not the numbers you should use.

By Scooter M.Published September 1, 2026Last reviewed September 1, 2026

Above 1,000 feet, water boils below 212°F, so canning processing times and pressures must increase. For water bath canning, add time. For pressure canning, increase the pressure. Recipes are written for sea level unless they say otherwise, and the adjustment is part of the tested process rather than an optional refinement.

This is the rule most often skipped, because it is invisible. Nothing about a jar processed without an altitude adjustment looks different, and nothing warns you. If you live above 1,000 feet, this page applies to every batch you have ever made and every batch you will make.

Why altitude changes anything

Water boils when its vapor pressure matches the surrounding air pressure. Higher up, the air pressure is lower, so water reaches that point at a lower temperature. At sea level water boils at 212°F; at 5,000 feet it boils at roughly 203°F.

Your canner is still boiling, and it is still at its maximum temperature — that temperature is simply lower. Since processing times were established for a specific temperature, less heat is reaching the food per minute, so the time has to go up. In a pressure canner the same logic applies to pressure: you need more pressure to reach the same temperature.

Water bath canning: add time

Altitude	Add to processing time
0 to 1,000 ft	No adjustment
1,001 to 3,000 ft	5 minutes
3,001 to 6,000 ft	10 minutes
6,001 to 8,000 ft	15 minutes
8,001 to 10,000 ft	20 minutes

The standard water bath adjustment. Where a specific tested recipe gives its own altitude table, use that instead — it takes precedence over any general chart.

Pressure canning: increase the pressure

Altitude	Weighted gauge	Dial gauge
0 to 1,000 ft	10 lb	11 lb
1,001 to 2,000 ft	15 lb	11 lb
2,001 to 4,000 ft	15 lb	12 lb
4,001 to 6,000 ft	15 lb	13 lb
6,001 to 8,000 ft	15 lb	14 lb
8,001 to 10,000 ft	15 lb	15 lb

Pressure canning adjusts pressure, not time. Weighted gauges have fixed steps, so above 1,000 feet you move to the 15 lb weight. Always follow the specific figures in your tested recipe and your canner's manual.

Sterilizing jars also changes

The 10-minute sterilizing boil gets 1 additional minute for every 1,000 feet above sea level. At 3,000 feet that is 13 minutes. See how to sterilize canning jars.

Finding your altitude

Search your town or county elevation. Most municipal and county sites publish it.
Your state extension service often lists altitudes by county specifically for canning, which is the most useful form of the number.
Phone GPS or a mapping app gives an approximate elevation, which is fine — the bands are wide.
When you are near a boundary, round up. More processing time is a quality cost. Less is a safety one.

Get the number once and write it inside the cover of your canning book. It does not change, and having it there removes the temptation to skip the step.

Common mistakes

Mistake	Why it happens	What it costs
Not adjusting at all	The recipe did not mention it and nothing looked wrong	Under-processing, invisible at the time
Adding time instead of pressure	Carrying over water bath logic	Still under-processed — the temperature was the problem
Using the altitude of a nearby city	Convenience	Can put you in the wrong band. Use your own
Adjusting a recipe that already adjusted	Double-counting a recipe's own table	Over-processing. A quality cost, not a safety one

One number, every batch

Altitude does not change between sessions, so this is a one-time lookup that applies forever in your kitchen. Find it, write it down, apply it every time. It is the cheapest correction in canning and the easiest to forget.

The gear that solves this

Two purchases make altitude adjustment less error-prone: a tested book with its own tables, and a canner that either handles it for you or is easy to read.

Next stepApply it to a water bath batch

Common questions

At what altitude do I need to adjust canning times?

Above 1,000 feet. Below that, recipes as written are correct, since they are developed for sea level.

How much time do I add for water bath canning at altitude?

5 minutes at 1,001 to 3,000 feet, 10 minutes at 3,001 to 6,000, 15 at 6,001 to 8,000 and 20 at 8,001 to 10,000 — unless your tested recipe gives its own table.

Do I add time or pressure for pressure canning at altitude?

Pressure. The time stays as written. Adding time instead of raising the pressure does not correct for altitude.

What pressure do I use at 5,000 feet?

15 lb on a weighted gauge, or 13 lb on a dial gauge, following the standard tables. Always confirm against your recipe and your canner's manual.

What if I am between two altitude bands?

Round up. More processing costs quality; less costs safety.

Do electric pressure canners need altitude adjustment?

Presto states its Precise digital canner does not, because the sensor handles it. Check the documentation for your specific model.

Sources

Product specifications are taken from each manufacturer’s own published page, cited on the product. We have not handled these products — how we pick.