UK Energy Bill Calculator

What This Tool Does

The UK energy billing system confuses most newcomers because you pay for two separate things:

• Unit rate (p/kWh) – What you pay for the energy you actually use
• Standing charge (p/day) – A daily fee just for being connected (you pay this even if you use zero energy)

This calculator helps you:

• Estimate your monthly bill (electricity + gas)
• Project your annual costs (helps with budgeting)
• See the breakdown: how much is usage vs standing charges
• Compare your bill to the UK average (£177/month dual fuel)
• Save your data to come back later
• Print as PDF for record-keeping

How to Use It (4 Simple Steps)

1) Load previous data (optional)

If you've used this calculator before:

• Click 📂 Load Previously Saved Data
• Your last inputs will auto-fill
• Update any values that changed

2) Enter your electricity details

You'll need three numbers from your bill or tariff:

• Monthly Usage (kWh) – How much electricity you used (check your bill or smart meter)
• Unit Rate (p/kWh) – The price per kilowatt-hour (Jan 2026 avg: 24.5p)
• Standing Charge (p/day) – Daily connection fee (Jan 2026 avg: 60.99p)

Don't have a bill yet? Start with the averages shown in gray text, then update later.

3) Enter your gas details (if you have gas)

Same three numbers for gas:

• Monthly Usage (kWh) – How much gas you used (Jan 2026 avg: 1,000 kWh)
• Unit Rate (p/kWh) – Price per kilowatt-hour (Jan 2026 avg: 6.24p)
• Standing Charge (p/day) – Daily connection fee (Jan 2026 avg: 31.43p)

No gas? Leave these fields blank or at zero.

4) Calculate and review

• Click Calculate My Bill 💰
• See your monthly and annual totals
• Review the detailed breakdown by fuel type
• Compare to UK average
• 💾 Save Results to load later
• 📄 Print PDF for your records

What You'll Need

For Electricity:

• ✅ Monthly usage in kWh (from your bill or smart meter app)
• ✅ Unit rate in p/kWh (from your bill or tariff details)
• ✅ Standing charge in p/day (from your bill or tariff details)

For Gas (if applicable):

• ✅ Monthly usage in kWh (from your bill – note: converted from m³)
• ✅ Unit rate in p/kWh (from your bill or tariff details)
• ✅ Standing charge in p/day (from your bill or tariff details)

Where to find these numbers:

• Your most recent energy bill (usually emailed monthly)
• Your supplier's website or mobile app
• Your welcome letter when you first signed up
• Price comparison sites (if researching switches)

Understanding Your Results

Monthly Total
This is your expected bill for one month based on the usage and rates you entered.
Example: £177.00 per month

Annual Total
Monthly × 12 = your expected yearly cost (helps with budgeting)
Example: £2,124.00 per year

Electricity Breakdown
Shows three numbers:
– Usage Cost: What your actual consumption cost (kWh × rate)
– Standing Charge: The daily fee × 30 days
– Total: Usage + Standing Charge

Gas Breakdown (if applicable)
Same three numbers for gas

Comparison to UK Average
The calculator compares your result to the UK average of £177/month (Jan 2026, dual fuel, typical consumption).
You'll see:
– If you're above average (consider comparing providers)
– If you're below average (good job!)
– If you're close to average

Why This Matters for Newcomers

1. Standing charges are confusing
In many countries, you only pay for what you use. In the UK, you pay:
– A daily connection fee (standing charge)
– PLUS your usage
This means even if you're away for a month, you still owe £40–50 in standing charges.

2. Low usage ≠ low bills
If you're in a small flat and barely home:
– Your usage might be very low
– But standing charges stay the same
– So standing charges become 40–50% of your bill
This calculator shows you exactly how much is standing charge vs usage.

3. Comparing tariffs is tricky
Two tariffs might show the same "estimated annual cost" but have:
– Very different standing charges
– Very different unit rates
If your usage doesn't match the "typical" estimate, your actual cost differs significantly.
This tool lets you enter YOUR actual usage to see real costs.

Common Questions

Why does gas show kWh when my meter shows m³?
Your gas meter measures volume (cubic meters), but your bill converts this to energy (kWh) because:
– Different gases have different energy content
– kWh is a standardized energy measurement
– It allows comparison with electricity
The conversion is done automatically by your supplier.
For this calculator: Just use the kWh shown on your bill (already converted).

Can I use this if I don't have a bill yet?
Yes! Use the default values shown:
– Electricity: 242 kWh at 24.5p/kWh, 60.99p/day standing
– Gas: 1,000 kWh at 6.24p/kWh, 31.43p/day standing
These are Jan 2026 UK averages. Update with your actual numbers when you get your first bill.

What if I have Economy 7 or other special tariffs?
This calculator assumes a single rate for electricity. Economy 7 has:
– Day rate (higher)
– Night rate (lower)
To estimate with Economy 7:
– Calculate your average rate: (day_kwh × day_rate + night_kwh × night_rate) / total_kwh
– Use that average in the calculator

Does this include VAT?
The calculator shows costs before VAT. UK energy bills have 5% VAT, so:
– If calculator shows £177/month
– Actual bill = £177 × 1.05 = £185.85

Why is my bill different from the calculator?
Possible reasons:
– You entered monthly usage but your bill is for a different period
– Your bill includes previous balance or payments
– Your meter readings were estimated (not actual)
– Additional charges (late fees, debt repayment)
– Different number of days in the billing period
The calculator estimates based on the inputs you provide. Always check your actual bill for the final amount.

Can I save my calculation?
Yes! After calculating:
– Click 💾 Save Results
– Your data is stored in your browser (private, local only)
– Click 📂 Load Previously Saved Data anytime to retrieve it
– Works even after closing your browser

Can I print my results?
Yes! After calculating:
– Click 📄 Print PDF
– Your browser's print dialog opens
– Choose "Save as PDF" from printer options
– Save to your computer

Best Next Steps

After using this calculator:

If your bill is higher than UK average:

1. Compare current deals on Compare The Market, Uswitch, or MoneySuperMarket
2. Check if you're on the best tariff for your usage pattern
3. Submit actual meter readings (if your bill was estimated)
4. Consider switching providers if you haven't in 12+ months

If your bill seems reasonable:

1. Save your results for future comparison
2. Set a reminder to check again in 3–6 months
3. Submit monthly meter readings to avoid estimated bills
4. Track your usage to understand seasonal variations

If you're confused about your bill:

1. Read: My First UK Energy Bill Made No Sense – I Researched Every Line
2. Check: Understanding UK Standing Charges By Region
3. Learn: How to Switch UK Energy Providers (First-Timer Guide)

Related Living Smart UK Tools

Use these together for complete energy bill management:

Before You Switch:
– Energy Savings Calculator → Compare two providers side-by-side
– Standing Charge Comparison → See regional differences
– Fixed vs Variable Tariff Calculator → Choose your tariff type

After You Switch:
– Usage Estimator → Estimate your kWh if you don't know it
– Energy Bill Calculator (this tool) → Track your new costs
– Tariff End Date Reminder → Get notified before fixed deal ends

For Understanding:
– UK Energy System Explainer → Suppliers vs network operators
– kWh Usage Tracker → Log your monthly usage
– Meter Reading Guide → Find and read your meters

Tips for Newcomers

Week 1: Get your baseline
– Use default values to see typical UK costs
– Understand the standing charge concept
– Find where your meters are located

Week 2–4: Get your first bill
– Enter your actual rates and usage
– Compare to your initial estimate
– See if reading was estimated or actual

Month 2+: Track and optimize
– Submit monthly meter readings
– Use this calculator each month
– Save results to track trends
– Compare providers every 3–6 months

Winter vs Summer
– Gas usage is much higher in winter (heating)
– Electricity relatively stable year-round
– Budget for higher winter bills (October–March)
– Your lowest bills will be May–September

Privacy & Data Storage

Your data stays private:

• All calculations happen in your browser (no data sent to servers)
• Save feature uses localStorage (stored locally on your device)
• No cookies or tracking
• No personal information collected
• You can clear saved data anytime (browser settings)

Saved data includes:

• Your 6 input values (kWh, rates, standing charges)
• Date/time you saved it
• Nothing else

Print feature:

• Opens your browser's native print dialog
• No data sent anywhere
• Save as PDF to your own computer
• You control where it's saved

💡 Pro Tip: Use this calculator monthly to track how your bills change with the seasons. Winter bills are typically 2–3x higher than summer due to heating. Budget accordingly!

Calculator last updated: January 2026 with current UK average rates
Rates shown are indicative – always check your supplier's current rates