The rules behind every result.

Primary sources

• Electricity and Gas (Standards of Performance) (Suppliers) (Amendment) Regulations 2026The instrument introducing smart-meter standards 1–3 from 23 February 2026.
• Supplier Standards of Performance Regulations 2015The underlying payment, exemption and appointment framework.
• Ofgem final decision on smart-meter Guaranteed StandardsPolicy reasoning and confirmation that GSOP1–3 proceeded.
• Citizens Advice: problems with your smart meterCurrent consumer explanation of the five-day duties and separate £40 payments.

How working days are counted

Working days exclude Saturdays, Sundays, Christmas Day, Good Friday and the bank holidays applying where the property is located. The first-installation standard uses 30 working days beginning with the request date. Five- and ten-working-day periods are conservatively calculated after the triggering event.

When a case turns on a single day, confirm the date with the supplier. The regulations do not provide a worked example for every wording variation.

Important boundaries

• Version one covers domestic premises in England, Wales and Scotland—not Northern Ireland or larger business sites.
• The five-day fault rule requires initial assessment, appropriate diagnostic action and an offer of written confirmation. It does not require full repair within five days.
• There is currently no automatic GSOP4 payment merely because a meter remains out of smart mode for 90 days.
• Supplier exemptions and disputed facts can change the result.
• This checks statutory minimum standards, not every consumer or contractual right.