I tracked one full canning season to the jar. Here is what a quart of home-canned tomatoes really costs, the honest version I promise across what I write about.
Do it safely first
Before the money math, get the method right. Tomatoes sit near the acidity line, so follow the National Center for Home Food Preservation guidance on canning tomatoes and add the recommended bottled lemon juice or citric acid. The full USDA Complete Guide to Home Canning covers safe processing times in detail.
The costs nobody counts
Jars are reusable, but lids are not. Add the energy to run a water-bath or pressure canner for hours, plus the tomatoes themselves if you did not grow them all.
Where it wins and where it loses
Grown from your own garden, canned in bulk, with reused jars, the per-quart cost lands well under the grocery equivalent, and the quality is not close. Buy the tomatoes retail, can small batches, and value your time at anything, and you are canning for love, not savings. Both are valid. Just know which one you are doing, and if the goal is savings, pair it with tracking every dollar.