Blackout Reveals Weak Spots in Portugal’s Mobile Networks for Expats

For thousands of foreigners who now call Portugal home—or who plan to land soon with a remote-work visa tucked in their passport—the nationwide power failure of late April was a rude reminder that connectivity is never guaranteed. When the lights went out, so did large swaths of the country’s mobile coverage. Yet the four operators did not stumble equally: MEO kept far more phones alive, Vodafone held on reasonably well, NOS wobbled, and budget newcomer Digi essentially disappeared. The episode has triggered a wave of regulatory scrutiny and fresh questions about how much redundancy Portuguese networks really have—and what customers, especially newcomers, can do about it.

A wake-up call borne of darkness

The outage struck shortly after sunset on 28 April, when a cascading fault on the Iberian grid severed electricity to millions from Porto to the Algarve. In less than two hours, battery backups at many cell sites drained, and by midnight roughly one in three mobile users nationwide had no signal. Emergency calls to 112 were rerouted through what capacity remained, illustrating how heavily Portugal now relies on its mobile layer after years of copper-line retirements.

A tale of four networks

Ookla’s post-mortem study, quietly circulated among telecom executives in June and later shared with ANACOM, paints a stark picture. At the six-hour mark, MEO customers were half as likely to go dark as NOS users, one-quarter as likely as Vodafone, and just one-sixth as likely as those on Digi. By the 24-hour point, up to 90% of Digi SIMs were still stranded. Vodafone’s headline numbers looked stronger than the narrative on social media suggested, largely because the company managed to keep 4G voice channels operational even as download speeds plunged 75%. NOS, which deactivated 5G to conserve power, landed in the middle of the pack.

Why the newcomer suffered most

Industry engineers point to "edge-to-core" fragility in Digi’s still-growing footprint. The Romanian-backed carrier rents tower space aggressively to keep prices low, but many of those sites rely on single-string power feeds and modest battery cabinets good for barely two hours. Inside the network core, analysts say Digi uses fewer geographically diverse routes, making it vulnerable when multiple municipalities lose power simultaneously. For price-savvy consumers the trade-off was laid bare: cheaper plans, thinner safety net.

Regulators sharpen their knives

ANACOM’s new chair, Sandra Maximiano, told parliament the blackout revealed “unacceptable gaps.” The regulator is drafting rules that would impose minimum autonomy targets for every cell site, hinting at fines for operators that fail to hit them. Meanwhile the Infrastructure Ministry has ordered sector-wide audits and flagged a revamp of the ageing emergency network, SIRESP, whose own failings compounded the night’s chaos. A technical report due at the end of July will explore satellite back-up channels, solar micro-grids and mandatory Cell Broadcast alerts so authorities can still warn the public when conventional voice collapses.

Operators balk at the price tag

At the 34th APDC congress this month, the chief technology officers of MEO, NOS and Vodafone struck a rare united front: equipping every Portuguese tower with 24-hour diesel generators and secure fuel logistics would be, in their words, “economically unsustainable.” The trio contends that such spending could slow 5G expansion and rural coverage goals. Digi, for its part, has remained largely silent. Privately, executives concede they must add redundant fiber paths and higher-capacity batteries, but no concrete timeline has surfaced.

What this means for foreign residents

Expats often juggle cross-border bank apps, e-Residency log-ins and health insurance portals that demand two-factor SMS codes. A prolonged outage therefore risks more than missed WhatsApp chats. Tech consultants now advise newcomers to activate eSIMs from two different carriers, keeping a Portuguese number for everyday use and a global roaming profile as a fail-safe. Another growing tactic is to stash a satellite messenger—Garmin inReach or Apple’s SOS feature—when hiking in the interior, where even on a good day LTE can be patchy.

Energy resilience is the wider battleground

Portugal’s government, keen to avoid a repeat, will unveil on 28 July a package to boost grid “black-start” capacity, battery storage and renewable micro-generation at critical sites, including telecom hubs. Officials are also studying whether communications masts could host their own solar arrays and lithium packs, lowering dependence on bulk diesel that proved hard to transport during the blackout. For now, though, the responsibility to stay reachable remains partly in the hands of consumers—and as last April demonstrated, the choice of network can make a very long night feel even longer.