Fitch upgrades Southern Water debt rating

(by Verity Mitchell)

Fitch Ratings has upgraded the rating of the senior secured debt of the financing company of Southern Water Services (SWS) to BBB from BBB-‌‌ with a stable outlook.

The upgrade reflected sustained equity support from funds managed by Macquarie Asset Management, now joined by Asterion Industrial Partners, which holds a 20% stake. SWS has made public its shareholders' intent to inject further equity to reach 65% reported net debt/regulated capital value (RCV) by the end of AMP8. This support comes amid an ongoing operational turnaround that is showing positive results as evidenced by improved Outcome Delivery Incentive (ODI) and environmental performance.

Fitch forecast about £30m in cumulative net in-period ODI rewards for AMP8 and ODI penalties of £237m, including amounts for AMP7's final two years. Fitch expected SWS to earn rewards from FY27, mainly driven by reduced pollution incidents and ODI framework improvements resulting from Southern's Competition and Markets Authority (CMA) appeal. Penalties resulting from poor customer perception of SWS will take time to rectify, and Fitch expected these penalties to persist for most of the AMP.

Alongside ODI framework improvements, Southern's CMA appeal resulted in a revenue increase of up to £165m (in real 2022-2023 prices) in AMP8. SWS will also benefit from £877m of contingency allowances which are included in Fitch’s rating case.

Fitch now expects SWS's post-maintenance interest coverage ratios (PMICRs) to be within its negative sensitivities in AMP8, although with low headroom. In FY26, SWS was ordered by Ofwat to undertake £13.5m of self-funded network improvements, mostly to sewer level monitoring and wetland restoration. Fitch viewed such capex as unavailable for debt service, therefore weakening SWS's PMICRs. However, it viewed this mandatory investment in the network as more beneficial to the business over the long term than a pure cash fine.

The sector continues to face a heightened risk of fines for operational and environmental underperformance, and Fitch forecasts included an additional £14m of fines for SWS.

The £1.2bn of equity committed to date demonstrates ongoing shareholder support. Fitch forecasts that a further £400m of fresh equity will be required to meet the public gearing target of 65% by 2030. Failure by the company to remain below 73% net debt/RCV, either by way of shareholder support or operational performance, would result in a downgrade.

Business risk remained moderately higher in AMP8 than in previous price controls, due to heightened environmental risk, increasing public scrutiny and higher clawback risk, which is linked to the price control deliverables mechanism.

The water sector is at a critical turning point. The Cunliffe Review recommendations, Water White Paper, and a forthcoming transition plan, expected later in 2026, add considerable uncertainty. The regulatory environment remained the most important building block in Fitch's analysis for determining sector debt capacity at a given rating.