If you are in a frugal state of mind, you know that it’s cost-efficient to pack a brown-bag lunch before you leave for work. Making food at home — especially if you’re packing last night’s leftovers — is cheaper than buying a quick meal from a restaurant.

But sometimes you don’t have time to grab anything. Maybe you ate every crumb of last night’s dinner, and there aren’t any leftovers. Or you meant to prepare a week’s worth of lunches on Sunday, but didn’t have time.

Whatever the reason, you didn’t carry lunch to work. Now you’re hungry and wondering how to protect your savings account by buying lunch as cheaply as possible. Here are a few tips.

Go to the grocery store

Grocery stores sell prepackaged and prepared lunch foods, which are often cheaper — and sometimes healthier — than lunch from a street vendor, food truck or quick-casual restaurant. If you need to buy a fast lunch, grab one of these meals. Popular options include salads, sandwiches, sushi rolls and low-carb wraps.

If you don’t like such prepackaged meals, choose an alternative. While you’re at the grocery store, grab a handful of “ingredients” that you can eat without any preparation, such as fresh fruit, nuts, yogurt, string cheese, crackers and granola bars.

If your office has a microwave, your options expand dramatically. You can pick up a frozen entree, canned soup or even root vegetables. Grab a sweet potato, chop it into small pieces and microwave it for a few minutes.

Stop by a smoothie shop

Can’t make it to a grocery store? If you’re in the mood for a light lunch, try a fruit smoothie. The cost is reasonable at around $3 to $5, depending on the size. So it won’t ruin your retirement savings dreams.

Smoothies can be healthy and filling, especially when they’re made with whole fruits and ice, with no added sugar. Ask for a scoop of protein powder or extra fiber to add some heft.

Look for restaurant deals

If no grocer or smoothie shop is conveniently located near work, a restaurant may be your only alternative.  Check daily deal apps like Scoutmob, Amazon Local, Groupon and LivingSocial, which often showcase half-off deals for restaurants. Many of these feature deals for quick, lunchtime eateries — perfect for your meal on the go.

Paula Pant helps people ditch the cubicle and live on their own terms. She’s traveled to 30 countries, owns six rental property units and hasn’t had an employer since 2008. Her blog, “Afford Anything,” is the gathering point for a tribe that refuses to say “I can’t afford it.” Follow Paula on Twitter: @AffordAnything.

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