My grandmother made this cooling summer side dish every August when the garden was overflowing. Just 4 ingredients for a crisp and tangy bite that goes perfectly with any barbecue.

This 4-ingredient cucumber onion salad is one of those simple summer recipes that feels like home, especially when the garden is producing more cucumbers than you know what to do with. It’s crisp, tangy, refreshing, and wonderfully easy to pull together, making it a classic warm-weather side dish that has been passed around family tables for generations.

Serve this salad nice and cold alongside burgers, grilled chicken, pulled pork, ribs, or hot dogs for an easy barbecue spread. It also pairs beautifully with baked beans, potato salad, corn on the cob, or a simple sandwich lunch, and the bright vinegar flavor helps balance richer main dishes.

4-Ingredient Cucumber Onion Salad

Servings: 6

Finished cucumber onion salad in a clear plastic container

Ingredients

4 cups thinly sliced cucumbers
1 small white onion, thinly sliced
1 cup white vinegar
1/2 cup granulated sugar

Sliced cucumbers, onion, vinegar, and sugar on a kitchen counter

Directions

1. Wash the cucumbers well and thinly slice them. Thinly slice the white onion into rings or half-moons, depending on your preference.

Freshly sliced cucumbers and onions on a cutting board

2. Place the sliced cucumbers and onions in a large bowl or container.

Cucumbers and onions combined in a large bowl

3. In a separate bowl or measuring cup, stir together the white vinegar and sugar until the sugar is mostly dissolved.

Vinegar and sugar mixed in a measuring cup

4. Pour the vinegar mixture over the cucumbers and onions, then toss gently so everything is evenly coated.

Cucumber onion salad being tossed in dressing

5. Cover and refrigerate for at least 1 hour before serving so the flavors can mingle and the vegetables stay cold and crisp. Stir once more before serving.

Plated cucumber onion salad served as a summer side

Variations & Tips

For extra chill: If you have time, let the salad rest in the refrigerator for a few hours. The cucumbers soak up more of the sweet-tangy flavor, and the salad becomes even more refreshing on a hot day.

For milder onion flavor: If your onion tastes especially sharp, soak the slices in cold water for 10 minutes, then drain before mixing them in. This keeps the crunch but softens the bite for picky eaters.

For a sweeter batch: Add an extra tablespoon or two of sugar if your family likes a more old-fashioned sweet-and-sour taste. You can adjust the balance after the salad sits for a bit and the flavors come together.

For best texture: Slice the cucumbers as evenly and thinly as you can so they pickle lightly and stay crisp. A mandoline works nicely, but a sharp knife does the job just fine too.