British Gas has agreed to pay £90mn in fines and penalties after Ofgem concluded a three-year investigation into its treatment of vulnerable customers. The regulator found the company breached licence conditions when forcibly installing pre-payment meters. Ofgem CEO Tim Jarvis said the company fell short in treating an unacceptable number of vulnerable customers who had meters installed without consent.

Under the settlement, British Gas will contribute £20mn to Ofgem's voluntary redress fund and write off up to £70mn of debt accumulated by vulnerable customers. Centrica, which owns British Gas and trades on the FTSE 100, faces both financial and reputational consequences from the regulator's findings.

The investigation, described by Ofgem as one of the most detailed and complex in its history, sets a precedent for how regulators will hold energy companies accountable for mistreatment of vulnerable customers. British Gas's debt write-off alone represents a substantial concession, while the £20mn redress fund signals regulatory intent to demand accountability beyond fines.