How to Can Diced Tomatoes for the Freezer

4 jars of diced tomatoes

Due to the variable pH levels occurring from one tomato to the next, it is generally not safe to can them using the water bath method unless extra acid is added. While doing this is perfectly acceptable, why bother with the fuss when you can simply freeze the jars instead? This easy instructional will show you how to preserve your summer bounty of tomatoes into a useful product you can use later. You’ll be thanking your past-self for the work done when you pop open a jar in February and feel the summer sunshine cascading out!

  • Prep Time55 min
  • Cook Time5 min
  • Total Time1 hr
  • Ready in1 Hr
  • Yield4 - 500ml jars


  • Approx. 6 lbs or 2.5 kg tomatoes**
  • Pinch of salt
  • 1 large basil leaf per jar (optional)



Prepare the 4 mason jars by washing them well with soap and water.

Rinse off any dirt or debris from the tomatoes.


plum tomatoes with the stem ends cut off

Trim the stem end off and cut a shallow ‘X’ into the base of each tomato.

plum tomato with the stem end cut off and a shallow x cut into the bottom


Bring a large pot of water to boil and prepare a large bowl full of ice water.


tomatoes dunked in boiling water

Dunk the tomatoes into the boiling water for 30 seconds to 1 minute.


tomatoes in an ice bath with the skins beginning to peel

Transfer to the ice water and let sit for another minute. It’s easier to do this in batches.


a pile of peeled tomatoes next to a pile of their skins

At this point, the tomato peels should be starting to slough off. Remove all of the peels from the tomatoes.


a knife dicing peeled tomatoes on a cutting board

Dice the tomatoes into 1cm pieces.


a large pot with lightly cooked diced tomatoes

Transfer diced tomatoes to a pot and add a good pinch of salt. Cook for about 5 minutes.


four mason jars with a basil leaf in each

Prepare your mason jars and put 1 basil leaf into each jar. 


4 mason jars full of diced tomatoes and a basil leaf

Add diced tomatoes to the jars, leaving lots of head room since they’ll expand once frozen.


4 jars of diced tomatoes

Screw on lids and let cool before transferring to the freezer, where they will last the winter.

*Plum tomatoes work best for this recipe as they contain less juice than their beefsteak counterparts. San marzano or Roma are good varietals. 

*This recipe can easily be doubled or tripled, you’ll need approx. 1.5 lbs/pint or 0.5 kg/500ml  of tomatoes per jar. 

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