SAN FRANCISCO (CBS 5) — Whether you carry it in a brown bag or in an eco-friendly lunchbox, bringing a sandwich from home can save you a lot of money, according to our Sandwich Survey.

The survey, which aimed to calculate the true cost of making a sandwich versus buying one, found sandwiches made at home are on average about 1/5th of the cost of ones made at a supermarket or deli.

The cheapest sandwich, by far, is peanut butter and jelly. Made at home, with name brand ingredients, a single PB&J sandwich cost just 62 cents. A tuna-salad sandwich came to $1.21, and a B.L.T. costs $1.29 to make. A cheese sandwich was $1.36, and an egg salad sandwich set us back just 90 cents.

CBS 5 ConsumerWatch purchased a bunch of sandwich ingredients at a Safeway in downtown San Francisco. Name brand ingredients like Skippy peanut butter, Smuckers Jelly, and Oscar Mayer Bacon were bought, in addition to Safeway-brand bread and eggs, which happened to be on sale. Then we assembled our sandwiches, and calculated the cost of the ingredients used in each one. Calculations are below.

CBS 5 ConsumerWatch got the idea from blogger Len Penzo, who conducts a similar sandwich survey every year in Southern California. Penzo said PB&J is almost always the cheapest sandwich to make at home, while the cost of other homemade sandwiches tended to vary from year to year, depending on the cost of ingredients.

Sandwiches purchased ready-made or made-to-order at supermarkets and delis in San Francisco can vary in price from $3.90 for a PB&J to $9.00 for tuna.

Here are the calculations for sandwiches in the survey.

Tuna ($1.21):
1/2 can Bumblebee Tuna 63 cents
2 T. Hellman’s Mayonnaise 5 cents
Tomato (2 slices) 18 cents
2 slices Whole Wheat Bread 35 cents

BLT ($1.28):
4 slices Bacon 60 cents
Lettuce 10 cents
Tomato (2 slices) 18 cents
Mayo 5 cents
2 Slices Whole Wheat Bread 35 cents

Egg Salad ($0.90):
2 Eggs 50 cents
2 T. Mayo 5 cents
2 Slices Whole Wheat Bread 35 cents

Cheese Sandwich ($1.36):
2 slices Kraft cheese 83 cents
Tomato (2 slices) 18 cents
2 Slices Whole Wheat Bread 35 cents

Peanut Butter & Jelly ($0.62):
2 T. Skippy Peanut Butter .10
2 T. Smucker’s Jelly .16
2 Slices Whole Wheat Bread .34

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