How to Can Tomatoes

A step-by-step guide on how to can tomatoes using either a pressure canner or water bath canning method. 

this Recipe

If you have a bumper crop of tomatoes, then you’ll want this easy guide for how to can tomatoes using either a pressure canner or a water bath canning method. The taste of fresh tomatoes cannot be beat — and with just a little time, you can transform juicy, summer tomatoes for use in chili, soup and stews all winter long. 

Vine-ripened, firm tomatoes are best for canning, and it’s not recommended to can any tomatoes from dead or frost-killed vines. 

If you are looking to can green tomatoes, then you don’t need to follow the below recommendations as they are more acidic than ripe red tomatoes and don’t need an additional acid source. 

Which acid to use for canning tomatoes? 

As tomatoes are a low-acid food, you’ll need to ensure a few things for canning safety. 2 tablespoons of bottled lemon juice of 1/2 teaspoon of citric acid is needed per quart of tomatoes to ensure safe acidity in whole, crushed or juiced tomatoes. 

For pints of tomatoes, you’ll need 1 tablespoon of bottled lemon juice or 1/4 teaspoon of citric acid. For safe canning, the amount of bottled lemon juice or citric acid cannot be reduced. Vinegar can also be used, but it imparts a flavor change that you may not like and therefore I recommend either bottled lemon juice or citric acid. 

The acid can be placed directly into the jars before adding in the tomatoes. Tomatoes prepared this way taste similar to canned tomatoes that you get at the store, but if you find that they have too much of an acid taste, you can add sugar as desired. As sugar does not change the pH level of canning, it’s safe to add as much sugar as you’d like to taste. 

Why bottled lemon juice? Can I use fresh? 

Fresh lemon juice is not the same as bottled lemon juice and is not interchangeable for canning. Bottled lemon juice has a consistent level of acidity, which makes it safer and more reliable than fresh lemon juice. 

You can purchase citric acid at some grocery stores or online. 

What You Need To Start

To can tomatoes, you’ll need canning jars in either quart or pint sizes. Mason jars are the best for this; I know that I love using weck-style canning jars to store food, but they are not recommended for canning. 

For old jars that have been used in canning before, you’ll need to purchase new lids for the seal though it’s OK to reuse old bands as long as they are not rusted. 

If you can recipes often, especially if you make my homemade salsa for canning regularly, then it’s worth purchasing a canning set of a canning funnel, jar lifter and magnetic lid lifter. 

You’ll also need fully ripe tomatoes; about 1 1/2 pounds of fresh tomatoes per pint jar and 3 pounds per quart jar. 

How to prepare tomatoes for canning

Whichever method you try, you’ll need to remove the skins first before canning. This is essential for safe canning as the skin may bacteria that can contaminate the canned tomatoes. 

Make sure to follow my step-by-step directions for how to peel tomatoes here. 

How to Sterilize Jars for Canning 

New canning jars are not sterile, especially as jars in a box can be contaminated by dust, debris or even glass from chipped jars. Jars that have been used before also need to be sterilized and cleaned before reused. 

In order to sterilize your jars, bring a large pot of water to a boil. Place the open, cleaned jars in a large pot of water and allow them to be submerged (covered) fully by boiling water for 10 minutes. 

When you are ready to fill the jars, remove them one at a time, carefully emptying the water from them back into the canner. You’ll want the jars to be hot before placing the tomatoes inside of them. 

Step By Step Instructions For Water Bath Canning Tomatoes without Added Liquid (Cold-Pack Method) 

Processing Directions for Normal Altitude and Above Sea Level 

Step By Step Instructions For Water Bath Canning Tomatoes (Hot-Pack Method) 

Processing Directions for Normal Altitude and Above Sea Level 

Using Boiling Water Canners Safely

You don’t need a specific water bath canner for this recipe, though it’s great if you have one! Any large pot with enough space to cover the jars with at least one inch of water works. To prevent the jars from sliding around when processing, place a silicone trivet on the bottom or a wire rack on the bottom. 

If you are new to canning, you’ll want to follow these steps to ensure safety with the water bath method. 

Fill the canner with water and bring to a boil. Load the filled jars into the canner (using either a jar lifter or a canner rack).

If the water level is not at least 1 inch above the jar top, add more boiling water. For process times that are longer than 30 minutes, like this tomato processing recipe, the water should be at least 2 inches above the tops of the jars. 

Cover the canner with its lid and bring back to a boil if not already there. Set a timer for the time recommended; you’ll want to maintain a boil throughout the entire process schedule time. It’s OK to reduce the heat as long as a boil is maintained for the entire process time. 

If the water level drops above the jars, then you’ll need to add more boiling water. 

Pressure Canning Instructions 

For processing tomatoes using a pressure canner, follow the same raw pack or hot pack prep directions for water canning, as above. An Instant Pot or multi-cooker is not the same as a pressure canner and is not recommended to be used. 

Pressure Canning Raw Pack Tomatoes without Added Liquid

Place the peeled tomatoes (whole or halved) into the sterilized jars, leaving 1/2 inch headspace and wipe rims of the jar with a dampened clean paper towel and place the lid on top. 

Place the jars in the pressure canner and follow any manufacturers directions about venting the pressure canner. 

For dial-gauge pressure canners, process pint and quart jars at 11 pounds pressure for 25 minutes. For those above 2,000 feet sea level, process jars at 12 pounds pressure for 25 minutes. Above 4000 feet sea level, process jars at 14 pounds pressure for 25 minutes. 

For weighted-gauge pressure canners, process pint and quart jars at 10 pounds pressure for 25 minutes. Above 1,000 feet sea level, process at 15 pounds for 25 minutes. 

Directions for Pressure Canning Hot Pack Tomatoes with Liquid

Place the hot tomatoes with liquid into the sterilized jars, leaving 1/2 inch headspace and wipe rims of the jar with a dampened clean paper towel and place the lid on top. 

Place the jars in the pressure canner and follow any manufacturers directions about venting the pressure canner. 

For dial-gauge pressure canners, process pint and quart jars at 11 pounds pressure for 10 minutes. For those above 2,000 feet sea level, process jars at 12 pounds pressure for 10 minutes. Above 4000 feet sea level, process jars at 13 pounds pressure for 10 minutes. 

For weighted-gauge pressure canners, process pint and quart jars at 10 pounds pressure for 10 minutes. Above 1,000 feet sea level, process at 15 pounds for 10 minutes. 

I hope that you enjoy this full tutorial on how to safely can tomatoes. I know it seems like a lot of steps, but once you do it once you’ll realize how easy it is and want to do it year after year or whenever you have an excess of fresh tomatoes. 

Once you try canning tomatoes, make sure to come back and make my canned salsa recipe and homemade spaghetti sauce canning recipe.