Prepayment price cap and direct debit prices since January 2016 (GB)


Source: Energylinx (Until May 2017) & Energyhelpline (June 2017 onwards).

Information correct as of: January 2019

This chart compares trends in prices since 2016 for a dual fuel customer paying by direct debit or prepayment. It shows both the market cheapest tariffs and average standard variable tariffs (SVT) for the two payment methods. The values are calculated for a customer with typical energy use.

From February 2017 the prices shown in the chart, including the level of the prepayment price cap, are calculated using the new TDCV values that entered into effect from 1st of October 2017 (see the methodology section for more details).

In practical terms, this means that the tariffs offered after February 2017 are likely to appear slightly lower than those before February 2017.  

Customers who get the Government’s Warm Home Discount and are on a standard variable or default tariff are protected by a ‘safeguard tariff’ set at the level of the prepayment price cap until the end of 2018, after which they will transfer to the default tariff price cap.

Policy Areas:

  • Electricity - retail markets
  • Electricity - wholesale markets
  • Gas - retail markets
  • Gas - wholesale markets

Data Table

Prepayment price cap and direct debit prices since January 2016 (GB)

DateSVT - direct debit (market average)SVT - prepayment (market average)Cheapest tariff - direct debit (all suppliers)Cheapest tariff - prepayment (all suppliers)Prepayment price cap

More information

At-a-glance summary

In April 2017, the prepayment price cap came into force, limiting the amount that suppliers can charge their prepayment customers. These customers tend to be unable to access the cheapest deals and are also more likely to be in vulnerable circumstances.

The cheapest prepayment tariffs available in the market have remained below the average SVT for a prepayment customer following the introduction of the prepayment price cap.

From 1 April 2018, the level of the prepayment price cap rose from £1,031 to £1,089 for a dual fuel customer who uses a typical amount of energy. This increase is mainly due to higher wholesale energy costs and policy costs to support low carbon forms of electricity generation. See our chart for further details,Breakdown of the prepayment price cap.

On 1 October 2018, the level of the prepayment price cap increased again. For more information, please see our page on the latest level for 1 October to 31 March 2019.

As suppliers increased their prepayment SVT prices to the new level of the cap, the differential between the average prepayment SVT and the market cheapest PPM tariff increased to £140 in May 2018. The differential has remained around this level since then, with the exception of September 2018 when the differential decreased to £102. At the end of December 2018, the differential was around £150. The average bill for prepayment customers on an SVT, which used to be amongst the highest in the market, was around £70 lower than the current standard variable tariff (SVT) paid by direct debit customers as of December 2018.

Relevance and further information

This chart helps us track the differences between the price a customer will pay depending on if they use prepayment (where prices are capped) or direct debit to pay their energy bills.

The prepayment price cap lasts until 2020. By then we expect the smart meter roll-out to give prepay customers access to better deals.

Customers who get the Government’s Warm Home Discount (WHD) and are on a standard variable or default tariff were protected by a ‘safeguard tariff’ set at the level of the prepayment price cap until the end of 2018, after which they were transferred to the default tariff price cap. The default tariff price cap came into effect on 1 January 2019, limiting the amount that suppliers can charge customers on default tariffs.

The default tariff cap has different levels set to reflect how customers pay, where they live and the type of energy meter they have. When transferred, WHD customers will be placed on the cheaper default cap level set for direct debit payment methods – it won’t matter how they pay.

You can find further information on energy price caps here.


  • We calculate the bill values associated with the different tariff types using a ‘typical medium domestic consumer’. As of October 2017, typical consumption values for a medium consumer are 12,000kWh/year for gas and 3,100kWh/year for electricity (profile class 1).  
  • All prices shown are for a dual fuel customer (i.e. where a customer takes gas and electricity from the same supplier).  
  • The market average SVTs are based on the prices of the 12 largest suppliers in the direct debit and prepayment segments. We have weighted the SVT of each supplier using an estimate of their total share of all SVT customers (for direct debit), and their total share of all prepayment accounts (for prepayment). We update the weightings every six months in January and July to reflect customer numbers four months prior to publication. The time lag is due to data availability. For example, the average given for 28 January 2017 uses weights based on customer numbers at 31 October 2016, while the average for 28 December 2016 uses weights at 31 March 2016. 
  • An SVT refers to a supply contract which is for a period of an indefinite length, and which does not have a fixed-term period applying to any of the terms and conditions. It’s an energy supplier’s basic offer. If a customer does not choose a specific energy plan, for example after their fixed tariff ends, they will be moved onto an SVT until they have chosen a new one. A customer can also make an active choice to select an SVT. 
  • We exclude tariffs with limited availability – such as tariffs only available to new customers (also known as ‘acquisition’ tariffs) or tariffs restricted to certain regions - when calculating the market cheapest tariff. This is so we give a representative picture of tariffs generally available to all customers across GB. 
  • We include tariffs available with ‘white label’ suppliers in our calculation of the cheapest tariffs. White label suppliers are organisations without supply licences that partner with an active licensed supplier to offer gas and electricity using their own brand. 
  • The cheapest tariff shown on the chart includes any collective switching tariffs after the first quarter of 2016. 
  • In all cases, the prices shown are based on suppliers’ tariffs averaged across GB regions. The level of the prepayment price cap is based on the values published on our website, adjusted to reflect current typical domestic consumption values, and to include VAT.

Date correct
January 2019
Policy areas