NEXTDC has signed binding documentation for $2.3 billion in new senior debt facilities, $500 million more than the commitments it announced in May, taking the data centre operator's total available senior debt to $8.7 billion once the deal reaches financial close, expected in mid-July.

The announcement, lodged with the ASX at 9:06am on Friday and marked price sensitive, is the debt leg of a funding stack the company has assembled at speed this year. Since April, NEXTDC has raised $1.5 billion through an entitlement offer at $12.70 a share, placed $1.7 billion in 100-year hybrid securities with Canadian investor La Caisse, and priced $750 million in wholesale notes. All of it is private capital chasing the same thing: contracted demand from hyperscale cloud and AI customers.

The numbers behind that demand are in NEXTDC's April market update. Pro forma contracted utilisation reached 667 megawatts at the end of March, up roughly 60 per cent in three months, driven by a record contract win of about 250 megawatts at its S4 site in Western Sydney. The forward order book sits at 544 megawatts. The company expects those existing contracts to generate more than $1 billion in annual earnings once built, against FY26 guidance of about $235 million, and it has flagged capital spending of about $5 billion in FY27 alone.

The upsize reflects continued strong support from a broad syndicate of domestic and international banks," NEXTDC said in Friday's announcement. When the facilities were first committed in May, the arranging group was eight banks: ANZ, Commonwealth Bank, ING, Mizuho, MUFG, NAB, HSBC and Westpac. The new money is earmarked for capital expenditure tied to recent contract wins, ongoing data centre developments and general corporate purposes, on margins the company says are broadly consistent with its existing debt.

Investors barely moved. NEXTDC shares were trading at $13.87 by late Friday morning, up 0.3 per cent, with the upsize flagged since May; the stock is up 21 per cent over 12 months against 2 per cent for the ASX 200, which was itself 0.5 per cent higher at midday.

The constraint is shifting, though. "Capital is no longer the bottleneck. Supply chain and grid connection now are," Stocks Down Under analyst Charlie Youlden wrote on Friday. That is the next test: an $8.7 billion debt stack buys land, shells and chillers, but it does not buy grid connections any faster. Financial close is due within the fortnight, and the S4 build runs through to the end of FY27.