Opus Energy has committed to paying £7 million in refunds, redress and goodwill payments after discovering it had overcharged 87,825 non-domestic customers over the past two decades.
This decision follows the identification of two faults in its billing system that led to customers being temporarily billed at incorrect tariffs or experiencing duplicate billing periods.
Opus Energy voluntarily reported the issue to the energy regulator, Ofgem, after an audit revealed the overcharges.
Between 2003 and 2023, these billing errors resulted in overcharges for thousands of customers.
Of the affected accounts, 93% were overcharged by less than £50 in total, while one customer, who has since received a refund, overpaid £102,000.
Opus Energy has confirmed that it has resolved the technical faults in its billing system and will be issuing refunds totalling £5.5 million to customers who were affected by the errors.
An additional £1.56 million will be paid as goodwill and redress.
Opus Energy has decided not to reclaim any amounts from customers who may have been undercharged due to these faults.
Current customers have already received automatic refunds, and former customers with refunds of £2.50 or more will be contacted to arrange payments.
Refunds below £2.50 and any unclaimed funds will be directed to the Energy Redress Fund.
