Yes — most healthy adults in London can drink softened water. However, it contains added sodium, so it may not be suitable for babies, people on low-sodium diets, or those with kidney disease. Many UK homes install a separate unsoftened or filtered tap for drinking and cooking.
That’s the short answer.
Now let’s break down what that really means for your home, your health, and your water system.
What Is Softened Water?
Softened water is tap water that has had hardness minerals — mainly calcium and magnesium — removed through a process called ion exchange.
In London, hard water is a major issue. Areas supplied by Thames Water are known for very high hardness levels, often above 250–300 mg/L (as CaCO₃). That’s why kettles scale up quickly and combi boilers lose efficiency.
A house water softener system works by:
- Passing hard water through resin beads.
- The beads trap calcium and magnesium.
- Sodium replaces those minerals.
- The system regenerates using brine during a regeneration cycle.
The result? Softer water for bathing, washing, and appliances — but with slightly higher sodium content.
Is Softened Water Safe to Drink in the UK?
According to guidance from the Drinking Water Inspectorate (DWI) and UK water regulations:
- Softened water is generally safe for healthy adults.
- The concern is not contamination.
- The concern is sodium content.
Softening does not introduce harmful bacteria if properly maintained. It does not make water toxic. But it does increase sodium levels depending on how hard your water was before treatment.
If you’re asking:
- Is softened water safe to drink?
- Is it ok to drink softened water?
- Can you drink softened water UK?
For most adults, the answer is yes — with context.
How Much Sodium Is Added?
The harder your water, the more sodium is added during ion exchange.
Approximate Sodium Addition
| Water Hardness | Sodium Added (approx.) |
|---|---|
| 5 grains per gallon | ~37 mg/L |
| 10 grains per gallon | ~75 mg/L |
| 20 grains per gallon | ~150 mg/L |
London is considered a very hard water area, often around 15–20 grains per gallon equivalent in some boroughs.
For comparison:
- A slice of bread contains 150–200 mg sodium.
- NHS recommended maximum daily sodium intake is about 2,300 mg.
So softened water contributes some sodium — but it’s not usually extreme.
Who Should Avoid Drinking Softened Water?
Even though soft water is drinkable for many, certain groups should not rely on it as their primary drinking source.
1. Babies on Formula
Softened water is not recommended for preparing baby formula. Infants require very low sodium intake.
2. People with Kidney Disease
Those with chronic kidney disease struggle to regulate sodium.
3. Individuals with Hypertension
If you’re on a strict low-sodium diet due to high blood pressure, speak to your GP.
4. Very High Hardness Homes
If your incoming water hardness is extremely high, sodium levels may rise significantly.
If any of these apply to you, installing a bypass tap or reverse osmosis system is a safer choice.
Softened Water vs Hard Water vs Filtered Water
Understanding the differences helps you make the right decision.
| Feature | Softened Water | Hard Water | Reverse Osmosis |
|---|---|---|---|
| Removes calcium & magnesium | Yes | No | Yes |
| Adds sodium | Yes | No | No |
| Removes contaminants | No | No | Yes |
| Good for appliances | Excellent | Poor | Excellent |
| Ideal for drinking | Conditional | Yes | Yes (best for purity) |
Softened water improves plumbing performance.
Reverse osmosis improves drinking purity.
Does Softened Water Taste Salty?
This is one of the most common concerns.
Softened water does not taste like seawater. The sodium added is small, and most people cannot detect it.
However, some describe:
- Slightly “flat” taste
- Less mineral freshness
Taste sensitivity varies.
Does Boiling Remove Sodium?
No.
Boiling water removes bacteria but does not remove dissolved sodium. If you are concerned about sodium content, boiling softened water will not fix it.
Is Softened Water Better Than Hard Water?
For plumbing and appliances — absolutely.
Hard water in London causes:
- Limescale in kettles
- Reduced combi boiler efficiency
- Scale formation inside pipes
- Shorter appliance lifespan
Softened water:
- Reduces scale formation
- Improves soap lathering
- Protects heating systems
- Extends appliance life
But for drinking alone, hard water is perfectly safe and contains natural calcium and magnesium.
Should You Install a Separate Drinking Tap?
In many London homes, the best solution is dual plumbing.
This means:
- Softened water for the whole house.
- Unsoftened cold tap for drinking.
- Or a reverse osmosis tap for purified water.
This setup is common in:
- South London
- Essex border areas
- Newly renovated properties
Reverse Osmosis as an Alternative
If you want softened water benefits without sodium in drinking water, install a reverse osmosis (RO) filtration system under the kitchen sink.
RO systems:
- Remove sodium
- Reduce total dissolved solids (TDS)
- Improve taste
- Filter contaminants
They are ideal for:
- Families with babies
- Health-conscious households
- Those asking, “Is water softener water drinkable long-term?”
London-Specific Considerations
London is one of the hardest water regions in the UK.
Hardness is measured in:
- mmol/L
- mg/L as CaCO₃
- grains per gallon
In many boroughs:
- Hardness exceeds 2.5 mmol/L
- Scale buildup is rapid
That’s why demand for water softener installation in London is high.
Local Pricing Guide
Water softener cost in London typically ranges:
- Basic electric system: £600–£1,200
- Premium non-electric system (e.g., Kinetico soft water systems or Harvey Water Softeners): £1,200–£2,000
- Installation: £300–£600
Some companies offer:
- Rent a water softener London plans
- Service packages
- Annual maintenance
How to Calculate Sodium in Your Softened Water
Here’s a simple method:
- Check your water hardness level from Thames Water.
- Convert hardness to grains per gallon.
- Multiply by approximately 7.5 mg sodium per grain per gallon.
Example:
If your water is 15 gpg →
15 × 7.5 = ~112 mg sodium per litre added.
This gives a realistic estimate.
Are There Side Effects of Drinking Softened Water?
For most people, no serious side effects occur.
However, possible concerns include:
- Increased sodium intake
- Reduced calcium and magnesium in drinking water
- Not ideal for baby formula
Drinking soft water side effects are mainly relevant to people with medical restrictions.
Is Softened Water Illegal in the Uk?
No.
Softened water systems are legal and widely used in London homes. Installation must comply with UK plumbing codes and British Standards.
Guidance from British Water and DWI focuses mainly on sodium thresholds for specific populations — not bans.
What About Pets?
Most pets tolerate softened water without issue.
However:
- Animals with kidney problems may require low-sodium water.
- If unsure, consult your vet.
Common Mistakes Homeowners Make
- Using softened water for baby formula.
- Not testing water hardness before installation.
- Ignoring regeneration maintenance.
- Skipping annual servicing.
- Not installing a bypass tap.
A small plumbing decision can make a big difference.
Decision Guide: Should You Drink Softened Water?
Ask yourself:
- Are you a healthy adult with no sodium restrictions?
- Do you live in a very hard water area in London?
- Are you concerned about appliance damage?
- Do you have infants at home?
If healthy adult → Drinking softened water is generally fine.
If baby or kidney condition → Install separate drinking tap or RO system.
If unsure → Speak to GP and installer.
FAQs
1. Can you drink softened water in London?
Yes, most healthy adults in London can drink softened water. However, it contains added sodium and may not be suitable for infants or those on low-sodium diets.
2. Is softened water safe to drink every day?
For most people, yes. Those with kidney disease or hypertension should consult a GP.
3. Does softened water contain salt?
It contains sodium, not table salt crystals. The sodium level depends on how hard your water was.
4. Is softened water safe for babies in the UK?
No. Softened water should not be used to prepare baby formula due to sodium content.
5. Can I drink water from a water softener?
Yes, if you are healthy and not on sodium restrictions. Many UK homes still prefer a separate drinking tap.
6. Does boiling softened water remove sodium?
No. Sodium remains in the water after boiling.
7. Is softened water better than hard water?
For plumbing and appliances, yes. For mineral intake, hard water contains natural calcium and magnesium.
8. How much does a water softener cost in London?
Typically £600–£2,000 for the unit plus £300–£600 for installation, depending on the system type.
Conclusion
So, can you drink softened water?
If you’re a healthy adult living in London, the answer is generally yes. The sodium added through ion exchange is usually moderate and safe within normal dietary limits.
However, softened water is not recommended for baby formula, strict low-sodium diets, or kidney conditions. In those cases, installing a bypass tap or reverse osmosis system is the smarter option.
In hard water areas like London, a water softener protects your plumbing, reduces scale, and improves appliance lifespan. The best setup for many homes is softened water for washing — and filtered or unsoftened water for drinking.
If you’re unsure, test your water hardness, calculate sodium levels, and speak to a qualified local installer before making your final decision.