Cheapest pay monthly energy tariff in the UK (how to find it)

If you want the cheapest total cost

Compare estimated annual cost (not just unit rates). Check exit fees, the fixed term length, and whether prices can change.

If you need budget certainty

A fixed monthly Direct Debit tariff can help with planning, but may include exit fees and may not stay best value if market prices fall.

If you’re on a prepay meter

You may see fewer pay monthly deals. It can still be worth comparing, and you may be able to switch to Direct Debit depending on your circumstances.

What you’ll need to compare properly: your postcode, whether you have a smart meter, your payment method, and (ideally) annual kWh usage for gas and electricity (from a bill or online account).

What to avoid: choosing based on a headline monthly amount alone. Direct Debit amounts can be set to smooth payments, and may change after a review.

Decision checklist: likely a good fit

• You can pay by monthly Direct Debit and want the broadest access to deals.
• You know your rough annual usage (kWh) or can estimate from a recent bill.
• You’re happy to pass a standard credit check (some suppliers require one for Direct Debit tariffs).
• You’re not tied into a fixed deal with high exit fees (or you’re near the end date).

Decision checklist: might not suit

• You prefer to pay when you receive a bill (pay on receipt), not a set Direct Debit.
• You have a prepay meter and cannot (or don’t want to) change payment method.
• You’re moving home soon and don’t want a fixed term with exit fees.
• Your usage is very low: a “low unit rate” deal with a high standing charge can cost more overall.

Scenario A: low electricity use flat (electricity-only)

Assumed annual usage

1,800 kWh electricity

Tariff 1 (low unit, high standing)

Unit: 24p/kWh; Standing: 70p/day

Tariff 2 (higher unit, lower standing)

Unit: 27p/kWh; Standing: 45p/day

Estimated annual cost

Tariff 1: (1,800×£0.24) + (365×£0.70) ≈ £688
Tariff 2: (1,800×£0.27) + (365×£0.45) ≈ £651

Takeaway: For low users, a lower standing charge can outweigh a lower unit rate.

Scenario B: typical dual fuel home (gas + electricity)

Assumed annual usage

2,900 kWh electricity + 12,000 kWh gas

Tariff 1 (fixed, slightly higher standing)

Elec: 25p/kWh & 55p/day; Gas: 6.5p/kWh & 35p/day

Tariff 2 (variable, slightly higher unit)

Elec: 26p/kWh & 50p/day; Gas: 6.9p/kWh & 30p/day

Estimated annual cost

Tariff 1: (2,900×£0.25)+(365×£0.55)+(12,000×£0.065)+(365×£0.35) ≈ £1,835
Tariff 2: (2,900×£0.26)+(365×£0.50)+(12,000×£0.069)+(365×£0.30) ≈ £1,876

Takeaway: For higher usage (especially gas), small unit-rate differences can dominate the total cost.

1) Standing charges can dominate

If you use less energy (small households, well-insulated flats, second homes), standing charges can be a large part of the annual cost. Always check both electricity and gas standing charges.

2) Direct Debit amounts aren’t the tariff price

Your monthly Direct Debit is an estimate to spread costs. It can change after supplier reviews (e.g., if you submit a meter reading or your balance changes). Compare tariffs on kWh rates, standing charges and estimated annual cost.

3) Exit fees and fixed-term timing

Fixed deals may have exit fees. Some suppliers allow you to switch without penalty near the end of a contract, but rules vary—check your current tariff terms before switching.

4) Multi-rate meters need the right tariff

Economy 7 (or other multi-rate tariffs) only make sense if a meaningful share of your electricity use is off-peak. If you’ve moved into a property with storage heaters, check whether your meter and tariff match how you actually use energy.

5) Prepay and debt restrictions

If you have a prepayment meter or energy debt, your options may be narrower. You can still compare, but eligibility and payment method changes depend on your supplier and circumstances.

6) “Extras” can distract from total cost

Bundles (e.g., smart gadgets, rewards, optional services) can add value for some people—but they don’t automatically make a tariff cheaper. Keep your comparison anchored on annual cost and contract terms.

Is Direct Debit always the cheapest way to pay?

Often, but not always. Many suppliers price Direct Debit tariffs competitively, yet the cheapest option depends on the specific tariff, your meter type, and your region. Always compare the full tariff costs, not just the payment method.

Why do prices vary by postcode?

Energy costs vary across Great Britain because of regional network charges and other cost differences. That’s why a tariff that looks “cheapest” nationally might not be cheapest in your area.

What’s the best way to compare pay monthly tariffs?

Use your annual usage in kWh (gas and electricity) and compare: unit rates, standing charges, tariff type (fixed/variable), contract length, and exit fees. If you don’t have kWh, use a recent bill to estimate.

Can I switch to a pay monthly tariff if I have a prepayment meter?

Sometimes. Some households can switch from prepay to credit/Direct Debit, but eligibility depends on the supplier and circumstances (for example, credit checks and any debt). If you’re unsure, compare options first and check with your supplier.

Will my monthly Direct Debit definitely stay the same?

No. Even on a fixed tariff, suppliers can review and adjust your Direct Debit amount based on usage, meter readings, and account balance. Your tariff rates may be fixed, but your monthly payment is still an estimate.

Should I choose a fixed or variable pay monthly tariff?

Fixed can help with planning and can be good value at the right time, but may include exit fees. Variable is more flexible but can change in price. The “cheapest” choice depends on current market pricing and your appetite for change.

Does a smart meter unlock cheaper pay monthly tariffs?

A smart meter can make billing more accurate and may enable access to certain tariffs, but it doesn’t guarantee cheaper prices. The cheapest tariff still depends on rates, standing charges and your usage pattern.

Are there any fees for switching energy supplier?

Switching itself is typically free, but you may pay exit fees if you leave a fixed tariff early (depending on your contract). Always check your current tariff’s terms before committing.

Page accountability

Written by

EnergyPlus Editorial Team

Reviewed by

Energy Specialist

Last updated

May 2026

How we assess “cheapest pay monthly tariff”

When we say “cheapest”, we mean the lowest estimated annual cost for a household’s inputs, not the lowest unit rate or the lowest headline monthly Direct Debit.

• Inputs we prioritise: postcode (region), meter type, payment method (monthly), fuel type (electricity-only or dual fuel) and annual kWh usage where available.
• What we compare: electricity and gas unit rates, standing charges, tariff type (fixed/variable/tracker), contract length, exit fees, and key eligibility constraints.
• Assumptions in examples: VAT at 5% is typically included in domestic tariff pricing; scenario maths is simplified to show trade-offs (rates are illustrative).
• Limitations: tariff availability can change quickly; some tariffs are limited to certain meter types (e.g., multi-rate) or require a successful credit check for Direct Debit.
• What we don’t do: we don’t promise a specific saving or claim a tariff will remain cheapest; we highlight trade-offs so you can choose confidently.