How Long to Boil Corn on the Cob

By The Recipes by Mom kitchen · Last checked October 21, 2026 · Not kitchen-tested; see how our recipes are made

Boiling is a fast and simple way to cook corn on the cob. Fresh, husked sweet corn requires only 3 to 5 minutes in boiling water to become tender and bright. If you are starting with frozen corn on the cob, it will need a few extra minutes, typically 5 to 8 minutes, to heat through completely.

The exact time depends on the corn’s freshness, its temperature before cooking, and your preference for tenderness. The cooking times provided on this page are a general guide for corn added to water that is already at a full, rolling boil.

How Long to Boil Corn on the Cob: time chart

Table source: Typical ranges from standard cooking practice, not an official chart. Ovens, grills and pieces vary: start checking at the low end of each range.

Good to know

• Salt in the water is optional; some cooks add it only after cooking
• Overcooked corn turns chewy

What changes the cooking time

Several factors influence how long corn on the cob needs to boil. The most significant is whether the corn is fresh or frozen.

• Fresh sweet corn cooks very quickly. The goal is to heat the kernels and lightly cook them to bring out their sweetness without making them tough. This usually takes just a few minutes.
• Frozen corn on the cob is typically blanched before freezing, so it is already partially cooked. The boiling time is longer because the corn needs to thaw and then heat all the way to the center.
• Older or starchier corn may require a longer boiling time, up to 8 minutes. As fresh corn ages, its natural sugars slowly convert to starch. Starchier kernels take more time in hot water to become pleasantly tender.

How to tell when corn is done

Since cooking times are a range, the best way to check for doneness is to look at and feel the kernels. There is no specific internal temperature for cooked corn; it simply needs to be hot and tender.

For fresh sweet corn, look for the kernels to turn a vibrant, bright yellow. They will appear plump and glossy. To check for texture, carefully pierce a kernel with the tip of a sharp knife or a fork. It should be crisp yet tender. If the kernels look shrunken or dimpled, the corn is likely overcooked.

For frozen corn, the primary goal is ensuring it is heated through to the core. Once it has boiled for the recommended 5 to 8 minutes, you can check it the same way as fresh corn by piercing a kernel to test its tenderness.

Overcooked corn becomes chewy and less sweet as the kernels’ cell walls break down and lose their delicate texture. It is better to cook it for a shorter time, as you can always return it to the pot for another minute if needed.

Tips for better results

Follow these simple practices for good results.

• Start with boiling water. Always bring your pot of water to a full, rolling boil before adding the corn. Adding corn to cold water and waiting for it to boil can lead to an inconsistent texture and may overcook the kernels.
• Use enough water. Make sure the corn cobs are fully submerged in the water. This ensures that all the kernels cook at the same rate. If the cobs are too large for the pot, you can cut them in half before cooking.
• Consider when to add salt. Some cooks believe that adding salt to the boiling water can make corn kernels tough. Others do not notice a difference. You can add salt to the water if you like, or simply salt the corn after cooking, along with butter or other seasonings.
• Do not cover the pot. Boiling corn uncovered allows you to monitor it easily and helps prevent the water from boiling over. Since the cooking time is short, covering the pot is not necessary to maintain the boil.

Sources and method

• USDA FSIS Safe Minimum Internal Temperature Chart
• Time ranges not marked as USDA are typical ranges from standard cooking practice

Last checked October 21, 2026.