Antin Infrastructure Partners has selected Citi as a second advisor to guide the sale of Portuguese water utility Indaqua, slated to start early next year, said sources familiar with the deal.

Citi joins Societe Generale, which had already been tipped for a sellside role last month, and the pair are expected to kick off an auction in Q1 2026, according to the sources. Citi already advised Indaqua’s previous owner, Bridgepoint, when it sold the company to Antin in 2020.

Antin is seeking over EUR 1.2bn from the sale of the business, which operates water and wastewater concessions in Portugal and Angola that serve 1.5 million people, sources said.

This would value the utility at more than 16x its roughly EUR 75m EBITDA expected for 2025, according to one source.

The deal has attracted preliminary interest from Taqa, the Abu Dhabi energy and water group that in August acquired GS Inima, a Spanish water concession operator, said two sources. Taqa signalled at the time that it would seek further targets to expand internationally.

Price expectations for Indaqua are higher than GS Inima’s valuation, however. Taqa bought the Spanish business for an EUR 1.2bn enterprise value, a multiple of around 11x its EUR 106m EBITDA in 2024.

Two other sources said KKR Infrastructure is among a number of infrastructure funds circling Indaqua. The US fund manager already attempted to buy the utility in 2023 in consortium with Equitix, EDF Invest and MEAG, in a deal that ultimately fell apart.

Further interest has come from Manila Water, a utility in the Philippines that has been actively expanding abroad, according to one of the sources. The company on 14 November announced its latest international deal, the entry into the Mexican market through the acquisition of a majority stake in local utility Agua de Puebla.

Antin and KKR declined to comment. Citi, Taqa and Manila Water did not respond to requests for comment.

The deal could attract other large infrastructure funds or consortia able to afford equity cheques of EUR 500m or more, given the size of the business, one source said.

Indaqua raised around EUR 358m of debt from Santander and Schroders Capital in September, which was described as “incremental financing”, and one source said bidders could seek to add further leverage.

Other strategic bidders are also likely to consider bids, with previous reports in the Spanish press pointing to France’s Veolia, IFM-backed Aqualia, and Acciona as likely candidates.

Antin bought Indaqua, then known as Miya Water, for an equity value of around EUR 625m, in 2020, when the business generated around EUR 45m of EBITDA.

The French infrastructure investor was eyeing a possible expansion in Puerto Rico to grow the business, but this did not materialise after a USD 300m water metering PPP in the country was cancelled in 2021.

Nevertheless, Indaqua has grown in the past few years and expanded into Spain, acquiring Mallorca-based water utility Fusosa in 2023.