Marinated Cucumbers, Onions, and Tomatoes is the perfect summer salad to highlight your garden haul or farmers market finds. With crisp cucumbers, juicy tomatoes, and zesty onions steeped in a simple vinegar-based dressing, this dish delivers bold flavor with minimal effort. It’s a refreshing side that suits any meal, from barbecues to weeknight dinners.

This Southern-inspired salad is more than just a bowl of vegetables—it’s a nostalgic mix of fresh produce and tangy-sweet marinade that gets better as it sits. Whether you chill it overnight or whip it up an hour ahead, Marinated Cucumbers, Onions, and Tomatoes is a crowd-pleasing classic you’ll return to all season long.

What Is the Marinated Cucumbers, Onions, and Tomatoes?

Marinated Cucumbers, Onions, and Tomatoes is a cold vegetable salad that combines sliced cucumbers, wedges of tomato, and thin onion slices in a seasoned vinegar marinade. The dressing typically includes water, vinegar, oil, sugar, salt, and pepper, allowing the vegetables to absorb the tangy-sweet flavors. It’s often served chilled and is popular in Southern cooking as a light, crisp, and hydrating accompaniment to grilled or fried dishes.

Why You’ll Love This Recipe

Bursting with freshness – peak-season veggies shine in every bite.
Quick to prep – just slice, mix, and let it marinate.
Make-ahead friendly – flavor improves as it chills.
Versatile side – pairs with grilled meats, fried chicken, or sandwiches.
Naturally gluten-free and vegan – fits a range of dietary needs.

This is the kind of salad that practically makes itself while you focus on the main course.

Ingredients for Marinated Cucumbers, Onions, and Tomatoes

To prepare this refreshing salad, you’ll need the following:

3 medium cucumbers, peeled and sliced
3 medium tomatoes, cut into wedges
1 medium red onion, thinly sliced
½ cup white vinegar
¼ cup water
¼ cup vegetable or olive oil
2 tablespoons granulated sugar
Salt and freshly ground black pepper, to taste

Optional: fresh herbs like dill or parsley for garnish

How To Make the Marinated Cucumbers, Onions, and Tomatoes

Step 1: Prepare the Vegetables

Peel and slice the cucumbers into thin rounds. Cut the tomatoes into wedges and thinly slice the red onion. Place all the vegetables in a large glass or ceramic mixing bowl.

Step 2: Make the Marinade

In a separate small bowl or jar, whisk together the vinegar, water, oil, and sugar until the sugar dissolves. Season with salt and black pepper to taste.

Step 3: Combine and Toss

Pour the marinade over the sliced vegetables. Gently toss to coat everything evenly. Make sure the marinade reaches all layers for full flavor.

Step 4: Let It Chill

Cover the bowl and refrigerate for at least 1 hour, preferably up to 4 hours. This allows the flavors to meld and intensify. Give it a stir just before serving.

What to Serve with Marinated Cucumbers, Onions, and Tomatoes

This crisp, tangy salad pairs beautifully with grilled proteins like chicken kabobs, pork chops, or barbecue ribs. It also complements heavier mains like fried catfish or macaroni and cheese by adding brightness and acidity. For lighter fare, serve it alongside sandwiches, quiche, or a simple frittata.

Top Tips for Perfecting Marinated Cucumbers, Onions, and Tomatoes

Slice evenly: Uniform slices help the veggies marinate evenly and look more polished on the plate.
Use ripe tomatoes: Choose tomatoes that are firm but juicy for the best texture.
Chill longer: The longer it marinates (up to 24 hours), the more developed the flavors.
Add herbs: A sprinkle of fresh dill, parsley, or basil can enhance the freshness.
Stir gently: Mix carefully to avoid crushing the tomatoes.

Storage Instructions

Store any leftovers in an airtight container in the refrigerator for up to 3 days. The vegetables will soften slightly over time but continue to soak up flavor. Stir before serving again. This salad is not freezer-friendly due to the high water content in the vegetables.