Fixed vs Variable Electricity Rate: How Each Works and a 5-Step Way to Choose

Fixed vs variable electricity rate: which one should you pick?

Choose a fixed rate if you want a predictable bill and would be upset by a price jump. Choose a variable rate if you can handle a bill that moves up and down, and you want flexibility to leave without a penalty. Neither plan is cheaper in every case, because the winner depends on where market prices go after you sign.

That is the short answer to the fixed vs variable electricity rate question. The rest of this guide shows how each one works, what the fine print can cost you, and how to test your own situation with simple maths. You do not need to be an expert. You need your last few bills and about twenty minutes.

One note first. This guide is for a global audience, so rules differ by country, state and region. In some places you can pick any supplier. In others the local utility sets the price and you have no choice. We explain both cases below.

How does a fixed electricity rate work?

A fixed rate locks the price of each unit of electricity for a set period. The unit is usually a kilowatt hour, or kWh. The period is often 6, 12, 24 or 36 months. During that time the price per unit does not change, even if wholesale energy prices rise sharply.

Your bill still changes with how much power you use. A cold winter or a hot summer will raise it. What stays put is the price of each unit. People often mix this up. Fixed rate does not mean fixed bill.

What is usually fixed:

• The energy price per kWh for the contract term.
• Often the daily standing or supply charge, but not always. Check this.

What may still change:

• Network, delivery or distribution charges set by regulators or grid companies.
• Taxes, levies and government fees.
• Your usage, which changes the total you pay.

Some contracts say charges set by third parties can be passed on to you. That means your "fixed" price could still move in a small way. Look for wording such as "pass-through" or "regulated charges may change".

The trade-off. A supplier takes on the risk that prices rise, so it usually builds a cushion into the fixed price. If the market stays calm or falls, you may pay more than you needed to. If the market spikes, you are protected. You are paying for certainty.

How does a variable electricity rate work?

A variable rate can change from month to month, or whenever the supplier or regulator decides. The price follows costs such as wholesale energy, network fees and policy charges. There is usually no fixed end date, so you stay on it until you switch.

Variable plans come in a few types. The names differ by country, so read the description, not just the label.

• Standard or default variable tariff. The supplier sets the price and may change it with notice. In some countries a regulator caps it.
• Indexed or market-linked plan. The price is tied to a published wholesale index plus a margin. It can move often.
• Time-of-use plan. The price depends on the hour. Evenings may cost more than nights. This is a different idea, because the price is known in advance by time of day. Some are fixed, some are variable.
• Dynamic or real-time plan. The price changes every hour or half hour. It suits people who can shift their usage and have a smart meter.

The trade-off. You take on price risk. In return you often pay less when markets are calm, and you can usually leave without an exit fee. You also get no protection when markets jump. Your bill can rise with only a short notice period.

Fixed vs variable electricity rate side by side

This table-style list shows the main differences in plain terms.

• Price certainty. Fixed: high for the term. Variable: low to medium.
• Chance of a lower price later. Fixed: you miss out if the market falls. Variable: you benefit if it falls.
• Protection from spikes. Fixed: yes, for the term. Variable: no.
• Exit fees. Fixed: common if you leave early. Variable: usually none or small.
• Budgeting. Fixed: easier. Variable: harder.
• Contract length. Fixed: set term. Variable: open ended, or monthly.
• Best for. Fixed: tight budgets, stable households, people who dislike surprises. Variable: people who move often, can cut or shift usage, or expect prices to drop.

Notice what is missing from the list. It does not say one is cheaper. A fixed price is a bet that prices will rise. A variable price is a bet that they will not. You are rarely able to predict this, so the better question is how much risk you can live with.

What hidden costs and fine print should you check?

Most comparison pages stop at the price per kWh. That is only part of the cost. Check each item in this list before you sign.

1. Standing or supply charge. This is a daily fee you pay even if you use no power. A plan with a low unit price and a high daily charge can cost more for a low-usage home. Example only: a charge of 0.50 per day is about 183 per year.
2. Exit or early termination fee. Many fixed plans charge this if you leave early. Find the amount and whether it is per month left or a flat fee.
3. Auto-renewal terms. When the fixed term ends, you may roll onto a more expensive variable rate. Put the end date in your calendar. Note how many days notice you get.
4. Introductory rates. A low first-period price may jump after a few months. Read the price for the full term, not only the headline.
5. Monthly fees and minimum usage fees. Some plans add a fee if you use less than a set amount of power.
6. Bill credits and conditions. A credit can look good but may need paperless billing, direct debit or a minimum spend.
7. Price change notice. For variable plans, find out how much notice the supplier must give and whether you can leave free when they raise the price.
8. Pass-through charges. Check which charges can change during a fixed term.
9. Meter and equipment needs. Time-of-use and dynamic plans may need a smart or interval meter. Ask if there is a fee.
10. Deposit. Some suppliers ask for a deposit depending on credit or history.

Ask for the "contract summary", "fact sheet" or "key terms" page. Many countries require suppliers to give one. It lists price, term, fees and exit rules in one place.

How do you choose between a fixed and variable rate? A 5-step method

Use these steps. They take your own numbers and turn the choice into a small calculation.

1. Find your yearly usage. Look at the last 12 months of bills and add the kWh. If you only have a few months, note that winter and summer can differ a lot. Use a full year if you can.
2. Write down your current price. Note the price per kWh and the daily charge. This is your baseline.
3. Get two or three quotes. Include at least one fixed and one variable plan. Use the same usage figure for each one.
4. Add everything up. Yearly cost equals kWh used times unit price, plus daily charge times 365, plus any monthly fees. Compare totals, not unit prices.
5. Test the downside. Ask: if the variable price rose 20 percent, could I pay the bill? If not, lean toward fixed.

Worked example. The numbers are round and for illustration only. They are not real prices.

• Your home uses 900 kWh a month, which is 10,800 kWh a year.
• Fixed plan: 20 cents per kWh for 12 months. Energy cost: 10,800 × 0.20 = 2,160.
• Variable plan: starts at 17 cents. Over the year the price moves between 15 and 26 cents.
• If the variable price averages 18 cents, you pay 10,800 × 0.18 = 1,944. You save 216 compared with fixed.
• If it averages 21 cents, you pay 10,800 × 0.21 = 2,268. You lose 108 compared with fixed.

The break-even point is simple. The variable plan wins if its average price over the term stays below the fixed price. Here that is 20 cents. You cannot know the future average, but you can ask how likely a rise is, and how painful it would be for you.

Now add an exit fee. Say the fixed plan has a 150 flat exit fee. Prices fall and a new plan would save you 3 cents per kWh. That is 10,800 × 0.03 = 324 a year, or about 162 for six months. Leaving with six months left would save only a little after the fee. This is why you should compare the fee against the possible saving before you move.

A quick rule of thumb.

• Lean fixed if your budget is tight, you plan to stay at the address for the whole term, and you value calm.
• Lean variable if you may move soon, can reduce or shift usage, have some savings as a buffer, or the fixed price is far above the variable one.

What are the most common mistakes, and when does this advice not apply?

Common mistakes

• Comparing only the unit price. A cheap unit price with a high daily charge can lose to a plan with a higher unit price.
• Locking in after a spike. Fear leads many people to fix right after prices rise. Prices may be at a peak. A fixed rate costs more when the market is high. If you need certainty, fix, but know what you are paying for.
• Forgetting the end date. The most expensive moment is often the day a fixed deal ends and you drop onto a default rate.
• Ignoring your usage change. If you add an electric car, a heat pump or a home office, your yearly kWh will rise. Fixed prices then protect more of your bill. Work out the new figure.
• Breaking a contract without checking the fee. Do the sum before you switch.
• Trusting a single estimate. Ask each supplier to use your actual usage, not a "typical home".
• Not reading renewal and change notices. Suppliers must usually tell you before a change. Open those emails and letters.

When this advice does not apply

• You have no choice of supplier. In many regions the local utility sets one regulated price. Then the fixed vs variable decision is not yours to make. You may still be able to change your usage, join a time-of-use scheme, or choose a green option.
• You have solar panels or a battery. Export payments, net metering and feed-in rules change the sums. A plan that is good for a normal home can be poor for you. Check how exports are paid.
• You rent and bills are included. If your landlord pays, you have nothing to choose.
• Your plan is a time-of-use or dynamic tariff. You need to compare when you use power, not only the average price.
• A regulator caps the standard rate. A cap may limit the downside of variable plans, but it does not guarantee a low price. Fixed plans may still be cheaper or dearer than the cap, so run the numbers.
• Business customers. Business contracts often have different rules, such as flexible procurement and long terms. Get advice for larger sites.

Can you switch later, and are there deals to use?

Switching is usually possible, but the cost depends on your contract. Variable plans are usually the easiest to leave. Fixed plans may charge a fee, though many suppliers let you move without a fee in the last weeks of the term. Ask about that window when you sign.

Before switching, do these things:

1. Check your current plan for an exit fee and notice period.
2. Take a meter reading on the switch date, and keep a photo.
3. Make sure the final bill from the old supplier matches your reading.
4. Set a reminder two months before your new plan ends.

On deals: our offer data was checked on 2026-11-06 and may have changed. At that date we held no electricity supplier offers. The offers we hold are for unrelated things, so we do not list them here. We would rather say so than place a deal that does not fit your question. When you compare electricity plans, judge them by total yearly cost and contract terms, not by a bonus or a sign-up gift.

A short disclosure. DealPortal may earn a commission if you use a link on our site, and this does not change the price you pay.

Frequently asked questions

Is a fixed or variable electricity rate cheaper?

Neither is always cheaper. A fixed rate usually includes a cushion for risk, so it often costs a bit more when prices stay flat or fall. A variable rate can cost less in calm times but can cost far more after a spike. Compare the total yearly cost using your own usage.

Is it a good idea to fix your electricity rate when prices are high?

It can protect you if prices keep rising, but you may lock in a high price if they fall. Fixing is mainly a way to buy certainty. If a surprise bill would cause real trouble, certainty may be worth the cost. If you have a buffer, a short fixed term or a variable plan may suit you better.

Can a fixed rate go up during the contract?

The unit price for energy should not change, but some charges can. Network fees, taxes and levies may be passed on, depending on your contract and local rules. Read the terms for "pass-through" or "regulated charges". Your total bill also rises if you use more power.

What happens when my fixed rate ends?

Often you move to the supplier's default variable rate, which may be higher. Some suppliers send a renewal offer first. Note your end date, and compare new deals a month or two before it. Check whether you can switch free in the final weeks.

Can I leave a fixed rate early?

Usually yes, but you may pay an exit fee. The fee can be a flat amount or depend on the months left. Compare the fee with what you would save on a new plan before you decide.

Which is better for a small apartment or low usage?

With low usage, the daily standing charge matters more than the unit price. Add the daily charge over a year and compare total costs. If you may move within a year, a plan with no exit fee is often the safer choice.

Do variable rates suit people with smart meters?

They can, particularly time-of-use or dynamic plans. If you can run the washing machine, car charger or heating at cheaper times, you may save. If your use is mostly in peak hours and cannot move, these plans may cost more than a flat fixed rate.

Read next

• How to Read Your Electricity Bill: Line by Line, Plus What You Can Change
• How to Switch Electricity Supplier: 8 Steps, Hidden Costs and Mistakes to Avoid
• How to Lower Your Electricity Bill at Home Without Losing Comfort: A Step by Step Plan
• Are Time of Use Electricity Plans Worth It? Who Saves Money and Who Does Not