In most cases, eating tartar sauce that’s past its printed date won’t make you sick, especially if it’s been refrigerated and shows no signs of spoilage. The date on a jar of tartar sauce is almost always a “Best if Used By” date, which refers to quality, not safety. According to the USDA, these dates indicate when a product will be at its best flavor, and with the exception of infant formula, they are not required by federal law and are not indicators of safety.
That said, tartar sauce is an egg-based condiment, and it can genuinely spoil. Whether you’re fine or end up with stomach trouble depends on how far past the date it is, how it was stored, and whether harmful bacteria had a chance to grow.
Why Tartar Sauce Can Spoil
Tartar sauce is built on a mayonnaise base, which means its core ingredients include eggs and oil. Commercial versions also contain acidic ingredients like pickles, capers, and lemon juice, which help slow bacterial growth. Store-bought jars typically include preservatives that extend shelf life further. But none of that makes tartar sauce shelf-stable forever, especially once you break the seal.
Once opened, the sauce is exposed to air, moisture, and whatever bacteria hitches a ride on the spoon or knife you dip into the jar. Over time, the emulsion breaks down, fats go rancid, and conditions can become more favorable for bacterial growth. An opened jar of tartar sauce stays good for about six months in the refrigerator. An unopened jar can last well beyond its printed date if it’s been stored properly, though quality will gradually decline.
The Realistic Health Risks
If the tartar sauce was only a few weeks or even a couple of months past its “Best By” date, was kept refrigerated, and looked and smelled normal, the odds of getting sick are very low. You might notice a slightly stale or flat taste, but that’s a quality issue, not a safety one. The USDA is clear on this: foods that don’t show signs of spoilage are still considered wholesome and safe to consume beyond their labeled dates.
The risk increases significantly if the sauce was left unrefrigerated for extended periods, if the jar has been open for many months, or if it shows visible signs of spoilage. In those situations, bacteria like Salmonella can potentially grow. Salmonella is associated with egg-based products and causes diarrhea (sometimes bloody), fever, stomach cramps, and vomiting, typically starting six hours to six days after exposure. For most healthy adults, symptoms resolve on their own within a few days. For young children, older adults, pregnant women, and people with weakened immune systems, the consequences can be more serious.
How to Tell If It’s Actually Spoiled
Your senses are a better guide than the date stamp. Here’s what to check before using tartar sauce that’s been sitting around:
- Smell: Fresh tartar sauce has a tangy, mildly pickled scent. Any sour, rancid, or off-putting odor means it’s done.
- Color: It should be pale cream to off-white. If it’s turned noticeably yellow, gray, or pink, the sauce has deteriorated.
- Texture: A slimy, grainy, or curdled consistency is a clear spoilage sign. Some minor separation is normal and stirs back in easily, but if the oil has permanently separated and won’t recombine, the emulsion has broken down too far.
- Mold: Any fuzzy spots, whether white, green, or blue, on the surface or around the lid means you should throw out the entire jar. Don’t scoop around it.
If everything looks, smells, and tastes normal, the sauce is almost certainly fine regardless of what the label says.
Homemade vs. Store-Bought
This distinction matters. Commercial tartar sauce contains preservatives and is manufactured under controlled conditions, giving it a much longer and more predictable shelf life. Homemade tartar sauce, which is typically just mayonnaise mixed with diced pickles, lemon juice, dill, and salt, lacks those preservatives. It spoils faster and should be used within a week or so of making it. If you ate homemade tartar sauce that had been sitting in the fridge for weeks, the risk of an upset stomach is higher than it would be with a commercial product past its date.
What to Do If You Feel Sick
Most food poisoning from a condiment like tartar sauce, if it happens at all, will be mild. You might experience nausea, stomach cramps, or diarrhea that passes within a day or two. The most important thing during that time is staying hydrated. Drink water, diluted fruit juice, broth, or sports drinks. If vomiting makes it hard to keep fluids down, take small sips of clear liquids rather than gulping. Saltine crackers can also help replace electrolytes.
Older adults and people with weakened immune systems should use oral rehydration solutions like Pedialyte if symptoms are severe. If you develop a fever or bloody diarrhea, those are signs of a more serious bacterial infection and you should see a doctor rather than trying to manage it with over-the-counter medications.
For most people, though, a squeeze of tartar sauce that was a bit past its prime is nothing to lose sleep over. The real danger zone is sauce that’s been left out at room temperature for hours, opened months ago and forgotten in the back of the fridge, or visibly off in any way. When in doubt, a new jar costs a couple of dollars.