Does water have sodium? The simple answer is yes. All water contains some sodium–the amount can change widely based on where the water comes from and how it’s treated. Some people need to watch sodium closely, especially if a health provider has told them to cut back. Others want the best water quality for their families. If you care about your water’s sodium level, you’re not alone. Learn what affects the sodium content in drinking water, why it matters, and how to make the safest choice for your home.
What Determines Sodium in Water?
Sodium gets in water in several ways. Understanding the sources of sodium can help you manage or reduce your intake.
Natural Sources
- Rocks and minerals: As groundwater moves through soil and rocks, it dissolves sodium compounds. This is why even well water often has some sodium.
- Natural salt deposits: Some regions, especially near the coast or salt basins, have higher sodium levels in their natural water sources.
Human Influences
- Road salt runoff: In colder climates, lots of salt is used to melt ice. Rain and melting snow wash this salt into rivers, lakes, and underground water.
- Sewage, fertilizers, and landfill leakage: Human waste and some fertilizers add sodium to ground and surface water. Landfills may also leak sodium compounds. Based on a fact sheet by the Massachusetts Department of Public Health, road salt runoff and landfill leakage are significant contributors to elevated sodium levels in drinking water.
- Water treatment chemicals: Some utilities use chemicals that contain sodium, like sodium hypochlorite or sodium bicarbonate, to treat drinking water.
- Home water softeners: Ion-exchange softeners swap minerals like calcium or magnesium for sodium. This process often increases the sodium in softened water.
How Much Sodium Is in Different Types of Water?
It's good to know the numbers—sodium content in water varies by type and location. Most drinking water contains only a small fraction of the sodium you eat in food, but in some cases, especially with softeners or natural deposits, levels can climb much higher.
Sodium Content in Drinking Water Types
Understanding how much sodium is in your drinking water is important, especially if you're monitoring your sodium intake for health reasons. While food is the primary source of sodium in our diets, water can still contribute—sometimes significantly, depending on the source and treatment method.
Tap Water (U.S. Average): 5–20 mg/L
In most U.S. cities, municipal tap water contains between 5 and 20 milligrams of sodium per liter. This is generally considered low and safe for most people. However, sodium levels can vary widely depending on the region. Coastal areas, regions that rely on desalinated water, and locations where road salt runoff enters groundwater supplies often have elevated sodium levels. In fact, some private wells have been recorded with sodium levels exceeding 160 mg/L, which may be a concern for those on low-sodium diets.
Bottled Spring or Mineral Water: 5–30+ mg/L
The sodium content in bottled spring or mineral water varies greatly depending on the natural source. Some contain less than 10 mg/L, while others—especially those from mineral-rich springs—can exceed 30 mg/L. Always check the label if you're watching your sodium intake, as some premium mineral waters intentionally retain higher levels of naturally occurring electrolytes, including sodium.
Bottled Distilled Water: Less than 1 mg/L
Distilled water is essentially free of sodium. The distillation process removes nearly all minerals, including sodium, making this water type ideal for individuals needing strict sodium restriction or those using water in sensitive appliances like CPAP machines or humidifiers. However, it lacks taste and beneficial minerals, so it’s not usually recommended for everyday drinking unless advised by a healthcare provider.
Filtered Water (Reverse Osmosis): Less than 1 to 5 mg/L
Reverse osmosis (RO) systems are highly effective at removing dissolved solids, including sodium. Most RO-treated water contains less than 5 mg/L of sodium, and often much less. For people looking to significantly reduce sodium intake from water, reverse osmosis is one of the best options available for home use.
Standard Carbon or Sediment Filters: No Effect on Sodium
Common household filters such as activated carbon pitchers or faucet filters are excellent for improving taste and removing chlorine, but they do not remove dissolved sodium. If you're using a basic filter and need to limit sodium, it's worth knowing that your water’s sodium content will remain unchanged.
Water Softener (Ion-Exchange Type): 20–300+ mg/L
If you have hard water and use a traditional ion-exchange water softener, the sodium content in your water can increase dramatically. These systems replace calcium and magnesium ions with sodium ions to reduce scale buildup, but in doing so, they can add anywhere from 20 to over 300 mg/L of sodium to your water—depending on the hardness level and settings. This can be problematic for individuals on sodium-restricted diets. In such cases, it’s advisable to drink unsoftened water or install a reverse osmosis filter for drinking purposes.
| Water Type | Typical Sodium Range (mg/L) | Notes |
| Tap Water (U.S. average) | 5–20 | Higher in coastal, salty, or road-salted areas. Some wells over 160. |
| Bottled Spring/Mineral Water | 5–30+ | Varies by source; check labels. |
| Bottled Distilled Water | Less than 1 | Almost no sodium; avoids minerals. |
| Filtered (Reverse Osmosis) | Less than 1 to 5 | Removes almost all sodium. |
| Standard Carbon or Sediment Filter | No effect | Does not remove dissolved sodium. |
| Water Softener (ion-exchange, typical) | 20–300+ | Sodium levels can increase by 40–300 mg/L. |
Tap water in most U.S. cities holds 5–20 mg of sodium per liter, but those near the coast or heavy road salt areas sometimes see much higher readings. Private wells, especially those close to roads, can easily exceed recommendations for people on sodium-restricted diets.
Is Sodium in Water a Health Concern?
Many people ask: Does sodium in your drinking water affect your health? For most people, water is a minor contributor compared to food. However, according to U.S. guidelines, the drinking water standard for sodium is 20 mg/L for individuals on low sodium diets. This level is considered protective for people with certain medical conditions such as hypertension or kidney disease.
Sodium in Drinking Water and Health
- Healthy adults: Usual tap or bottled water levels are not a health concern.
- Sensitive groups: People with hypertension, heart disease, or chronic kidney disease may need to keep sodium very low. A doctor or dietitian will often recommend that the sodium in drinking water be less than 20 mg/L for these groups.
- Children and infants: High sodium isn’t recommended for young children or formula preparation.
Drinking Water Sodium Limits
| Guidance/Regulation | Sodium Level (mg/L) | Who Is It For? |
| U.S. EPA Advisory | 20 | Very low-sodium diets |
| Florida Department of Health | 160 | People on restricted diets |
| Typical U.S. Tap Water | 5–20 (average) | General population |
| Private Wells/Road-Salt Regions | Up to 300 | Check with local report |
Real-World Example
If you drink 2 liters (8 cups) of water a day at 20 mg/L sodium, that’s only 40 mg—less than 2% of the average adult’s daily sodium intake from food. Compare that to foods: A slice of bread may have 150–200 mg, soup may have over 600 mg per serving.
How Do I Know My Water’s Sodium Content?
Curious about how much sodium is in your water? Several easy steps can help:
Step 1: Local Water Quality Reports
Public utilities are required to share water quality Consumer Confidence Reports each year. These often list sodium and other minerals.
- Search your town’s name plus “water quality report.”
- Contact your city or county health department for help if you can’t find the report.
Step 2: Test Your Water
- Lab Analysis: For private wells or softened water, a certified laboratory offers the most reliable sodium test.
- Home Test Strips: Some test strips exist, but they’re less accurate.
Step 3: Use an Online Calculator
Some online tools let you estimate your water’s sodium based on local utility data. They can help you figure out your daily intake using your home’s sodium level and how much water you drink.
Step 4: Call Your Utility or Health Department
If your water isn’t from a big city system, ask your local public water supplier for specific sodium results. For private wells, contact your county or state health department.
How to Reduce Sodium in Drinking Water
Is your household water showing a high level of sodium? There are options—but some methods work much better than others. Understanding the pros and cons of each method is key to selecting the right water system for your household’s needs.
Reverse Osmosis (RO) – The Most Effective Choice
Reverse osmosis (RO) is considered the gold standard for sodium removal in residential water treatment. It works by forcing water through a semi-permeable membrane that blocks sodium ions and other dissolved solids. In fact, RO systems can remove up to 99% of sodium, making them one of the most reliable options for people on sodium-restricted diets or those concerned about salt intake in general.
One of the main advantages of RO water is that it’s nearly sodium-free and also free of many other impurities, including heavy metals, nitrates, and some PFAS compounds. If you’re wondering, “Does purified water have salt in it?”—the answer depends on the purification method. In the case of reverse osmosis, purified water has virtually no sodium or salt, making it a top recommendation for households with health-related sodium concerns. If you're asking “what water filter removes sodium,” reverse osmosis system is the clear winner among home-use options.
RO filtration systems are particularly helpful when your home uses a water softener, which adds sodium to the water in the process of removing hardness minerals. A common solution is to install an RO filter at the kitchen sink, ensuring your drinking and cooking water remains low in sodium even if your entire house uses softened water.
Distillation – Effective but Less Practical
Another effective method for sodium reduction is distillation. This process boils water and then condenses the steam into a separate container, leaving salts and minerals behind. While distillation effectively removes sodium, it’s much slower and less convenient for daily household use. It’s better suited for small-scale applications, such as filling a humidifier or providing very low-mineral water for specific medical devices.
If you’ve ever wondered, “Does purified water have sodium?”, distilled water is another form of purified water that contains virtually none. Like RO, it’s a viable choice for people needing extremely low-sodium water, but it lacks the convenience and flow rate of modern RO systems.
Carbon and Sediment Filters – Not Effective for Sodium
Standard carbon or sediment filters, such as those found in pitcher systems or faucet attachments, are helpful for improving taste, removing chlorine, and trapping sediment. However, they do not remove sodium or other dissolved salts. If your primary concern is reducing salt content in your water, these filters won’t help. They’re often used in combination with RO systems, but on their own, they’re not a solution for sodium.
Water Softeners – May Make It Worse
Ironically, water softeners—which are common in households with hard water—can increase the sodium content in your drinking water. These systems work through ion-exchange, replacing calcium and magnesium ions with sodium. While this improves soap performance and reduces scale buildup, it may raise sodium levels significantly, often to levels unsuitable for people on a low-sodium diet. If you're using a softener, it’s best to bypass it for drinking water or pair it with a reverse osmosis unit at the tap. Otherwise, your water may contain excess sodium, which could be problematic for people trying to manage their sodium intake due to health concerns.
Boiling Water – Not a Solution
Boiling water does not reduce sodium. In fact, it concentrates the sodium as the water evaporates, leaving more salt behind per liter. So if you're thinking of boiling your water to reduce sodium content, it’s not only ineffective—it may make the problem worse.
Quick Comparison for Treatment Option at Home
| Treatment Option | Removes Sodium? | Notes |
| Reverse Osmosis (RO) | Yes (up to 99%) | Most effective for home use. RO uses a special membrane to trap sodium ions, providing water that is not high in salt content. Key advantage: produces very low-sodium purified water. A main reason people choose RO is for life on a sodium-restricted diet. |
| Distillation | Yes | Also highly effective. Runs water as steam, then condenses it, leaving salt behind. Good for small amounts but less convenient for daily household needs. |
| Standard Carbon/Sediment Filter | No | Does not remove sodium. Good for chlorine, taste, and odor, but not for minerals or salt. |
| Water Softener (ion-exchange) | No; adds more sodium | Softens water by exchanging calcium/magnesium for sodium—may greatly increase sodium content. People on tight sodium control should avoid softened water for drinking/cooking. |
| Boiling Water | No; raises sodium concentration | Water evaporates but sodium stays, making remaining water slightly saltier. |
Quick Tips for Lower Sodium Water
- Use an RO system or distillation unit for drinking and cooking water if you need the lowest sodium.
- If your water comes from a softener, bypass it for kitchen taps or install a separate RO filter just for drinking.
- Check bottled water labels if you use bottled water—mineral and sparkling types sometimes have higher sodium.
Choosing the right filtration method is essential for maintaining optimal drinking water quality, especially if you're aiming for low sodium water to support health or dietary restrictions.
Sodium in Water by Region: U.S. and Global Patterns
Sodium levels can shift a lot depending on your location and the local environment. Here’s a look at some regional patterns.
U.S. Sodium Levels
| Area Type | Average Sodium Range (mg/L) | Description |
| Most U.S. Cities | 5–20 | Average range; safe for healthy adults |
| Coastal States | 20–160+ | Higher from natural salt and road salting |
| Road-Salted Areas | 20–300+ | Road de-icing increases levels; especially wells |
| Private Wells | Unpredictable (5–300+) | Can be high, especially in farm or road-heavy areas |
- Some Florida, New York, and Massachusetts wells have over 160 mg/L due to sand, salt air, and human impacts.
- Rural wells near big roads or farming areas also risk higher sodium.
Global View
- Some international regions, especially those with saline groundwater or rock salt layers, may see levels over 250 mg/L, far above U.S. averages.
Expert Insights
A public health nutritionist has said:
“Most people get far more sodium from food than from water, but those advised by a doctor to sharply restrict sodium should always check their water supply—even private wells. Reverse osmosis or distilled water is best if you need to keep sodium intake as low as possible.”
To learn more or get authoritative guidance, ask your doctor or contact your local health department.
Conclusion & Key Takeaways
- All water contains some sodium—the amounts vary due to both nature and human activities.
- The sodium in drinking water is rarely a problem for healthy adults. Most sodium in your diet still comes from processed foods.
- If you have hypertension, kidney trouble, heart disease, or use a sodium-restricted diet, your water should have less than 20 mg/L. Get your water tested if you use a private well, live in a heavily road-salted area, or use a water softener.
- Reverse osmosis is the most reliable low-sodium filter choice for your health. Boiling and standard filters will not help remove sodium.
- Always review your local water report and consult your health care provider if you’re worried about sodium intake.
FAQs
1. Does boiling water remove sodium?
No, boiling water does not remove dissolved sodium - in fact, it does the opposite. Sodium is a mineral, and heating doesn't remove it at all. While the water boils and turns to water vapor and runs off, the sodium stays firmly in the water. As the water continues to evaporate, sodium is becoming more and more concentrated, simply become a concentrated version of the “salt water”, away from the standard of clean water farther and farther. It is not the same thing as sterilizing and evaporating certain chemicals. Bacteria are afraid of high temperatures, and some chemicals evaporate when heated. But sodium as a stable ionic compound, no matter how the water boiling and rolling, is firmly in the water. If you have high blood pressure, kidney disease or want to control dietary sodium intake, boiling water to remove sodium is a waste of time. Really want to get rid of sodium in the water, you have to use professional filtration equipment, such as reverse osmosis water purifier, distillation device or deionization equipment, these are the reliable ways that water can be de-sodiumed.
2. Is all bottled water low in sodium?
Not necessarily. Although many bottled water brands offer low-sodium versions, not all bottled water meets the “low-sodium” standard, especially mineral and spring water. Most of these waters come from underground sources and naturally contain a number of minerals, sodium being one of them. Some brands also use the mineral content as a selling point, promoting the concept of “electrolyte fortification”, saying it improves taste or is suitable for post-exercise rehydration, when the sodium content of the water may be more than 30mg / liter! There are exceptions to this rule - distilled water and pure bottled water are virtually sodium-free, as most of the minerals are filtered out during the manufacturing process. If you're on a low-sodium diet due to high blood pressure, kidney problems, or if your doctor recommends a low-sodium diet, be sure to read the nutrition label on your bottled water! In the U.S., any bottle that contains more than 5 mg of sodium per bottle must be clearly marked on the label, so pay close attention when you buy.
3. Do common filters remove sodium?
Most of them don't work! Common devices like activated carbon water filters, faucet water filters, and basic sediment filters simply don't remove sodium. Sodium exists in water as ions, and the particles are so ridiculously small that the precision of a common water filter just can't catch them. These devices are mainly used to improve the taste of water, remove residual chlorine, or filter rust, sediment and other large particles of impurities, but against the dissolved salts in the water is useless. If you are trying to reduce your sodium intake with a regular water filter because you have high blood pressure or want to control your dietary sodium intake, you're looking for the wrong way to do it. To solve this problem, you have to use more specialized filtration means - reverse osmosis (RO), distillation or deionization equipment, which can really drive sodium ions out of the water. Reverse osmosis water purifiers, in particular, are the most used and most convenient in home kitchens. It's the right choice if you want to drink low-sodium water!
4. Can sodium change the taste of water?
In most cases, the sodium content of tap water is so low that it does not significantly affect the taste. The average municipal water supply has a sodium content of 5 to 20 mg/liter, which is too low for the average person to taste in water. However, if the sodium content exceeds 150 to 200 mg / liter, the situation is different, people with a sensitive sense of taste, or people who are used to drinking soft water, a mouthful of water can detect a slight salty taste, or similar to the strange taste of minerals. Areas by the sea, water treated with water softeners, and next to natural salt mines, the sodium content of water in these areas can easily exceed the limit. And that strange taste will be more pronounced when you use this water for cooking, making tea, or brewing baby formula.
However, by tasting the water to determine the amount of sodium, this approach is not very reliable. Some water is obviously not low in sodium, but it doesn't taste abnormal, especially if other minerals such as chloride, calcium or magnesium are added to balance it out. So if you really want to know how much sodium is in your water, it's more reliable to test or check a water quality report than to rely on taste to detect sodium content.
5. Is softener-treated water salt-free?
In fact, the situation is not so simple. Although some devices on the market are called “salt-free water softeners”, there is a difference between them and traditional water softeners. The common traditional ion-exchange water softeners use table salt (sodium chloride) to replace hard minerals in the water, such as calcium and magnesium, so the softened water will have extra sodium in it. This means that the water you drink will have a higher sodium content than untreated tap water, which can range from 20 milligrams per liter (mg/l) to more than 300 mg/l, depending on how hard the water in your home is and how often the water softener is regenerated. “Salt-free” water softeners, better known as “water conditioners”, are not really water softeners. The devices use potassium or Template Assisted Crystallization (TAC) to stop scale formation but they do not remove hardness minerals or add sodium to the water. Notice that they also do not remove the naturally occurring trace amounts of sodium that are present in the water supply. If you are controlling your sodium intake, then softening water to drink alone may not be appropriate. For low-sodium drinking water, it is best to bypass the water softener at the kitchen faucet or have a reverse osmosis water purification system for a safer and more secure water supply.
References
Massachusetts Department of Public Health. Sodium in Drinking Water Fact Sheet. https://www.mass.gov/doc/dph-fact-sheet-sodium-in-drinking-water/download