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. This differential between the average SVT and the cheapest prepayment tariff has remained over £100 since April 2018. In May 2019, this differential decreased from £218 to £189 as the cheapest prepayment meter tariff increased by £29.
On 1 April 2019, the level of the prepayment price cap increased from £1,136 to £1,242 for a dual fuel customer who uses a typical amount of energy. This increase was mainly due to higher wholesale energy costs and network costs.. For more information on the latest updates, see our chart Breakdown of the prepayment price cap.
Relevance and further information
This chart helps us track the differential between the average prepayment SVT and the market cheapest PPM tariff price a customer will pay if they use prepayment to pay their energy bills. Both prices are compared with the prepayment price cap that currently apply to all prepayment customers, excluding those on ‘interoperable’ smart meters.
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 prepayment segment. We have weighted the SVT of each supplier using an estimate of 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.