International fax down: the 2026 plan B

Short answer: when a cross-border fax fails repeatedly even though it went through last week, the cause is almost always at the receiving end, not at yours. Three scenarios cover nearly every case: the foreign recipient has migrated their line (switch to fibre, end of copper, new PBX) and their fax machine was left behind; the recipient has dropped fax without saying so, leaving the number printed on their correspondence; or a temporary outage has hit the local network in the destination country. Before buying new hardware or changing services, read the failure report (invalid number ≠ no answer ≠ negotiation failure), test the same number with a voice call, then switch to the backup channel specific to the country: eBox and Belgian Mobile ID in Belgium, beA or plain email for Germany, Spain's registro electrónico (electronic register), PEC and now the domicilio digitale (digital domicile) in Italy, ePortugal in Portugal, the secure portals of IRCC, the CRA and Revenu Québec in Canada. A fax that no longer goes through doesn't cancel your deadline: it's your proof of attempt that saves it.

About MondialFax. This article is an informational guide, with no connection to any telecom operator, government body or official directory. MondialFax sends faxes free of charge and without registration to seven destinations (France, Belgium, Germany, Spain, Italy, Portugal, Canada) from a browser, with a daily sending limit. It does not assign a number and does not provide reception. See the supported countries page and the directory of dialling codes.

Why a cross-border outage is unlike any other

Within a single country, a failed fax is quick to diagnose: you call the recipient, check the wall socket, try again. As soon as a border is involved, three layers stack up and each one can fail without warning.

The first layer is yours: your sending service, your connection, the file you uploaded. The second is international transit: your operator or your online fax provider hands the call over to one or more transit carriers, often over VoIP, until it reaches the terminating operator. The third is the local loop in the destination country, the one changing fastest in 2026: Germany has completed most of its All-IP switchover at Deutsche Telekom, Belgium is pressing ahead with the shutdown of Proximus's copper, Spain has closed its copper exchanges with Telefónica, Portugal is moving forward with MEO, Italy is adjusting its deadlines and Canada is letting operators withdraw copper pairs region by region under the watch of the CRTC.

The practical consequence: the same number, dialled from France or Quebec, can work on Monday and fail on Thursday without a single setting changing at your end. We described this shift country by country in the end of copper outside France; what follows is the logical sequel: what to do the same day, when a document has to go out before a deadline.

Read the failure report before anything else

A transmission report isn't a formality, it's your measuring instrument. The wording varies from one service to another, but it falls into four families, and each one points to a different layer.

The classic trap is still the first one: a number copied in the national format of the destination country. From France, you dial 00 + country code + the number without its leading zero; from Canada, the international prefix is 011. If in doubt, start by revisiting the number format that works before concluding there's an outage: a 00 49 030 … fails every time and has nothing to do with a network failure.

The other three families can be told apart with a simple, free test that is far too rarely done: calling the fax number as a voice call. If a modem tone answers, the machine is alive and the problem is in transit. If a human voice answers, the extension has been reassigned. If it rings out, or a foreign operator's message cuts in, the line is dead. To keep track of these attempts, a simple spiral notebook kept by the machine is enough to record the exact time, the transmission ID and the response you got — that log is what counts later on, not your memory.

The three most common failures

1. The recipient migrated their line and nobody mentioned it

This is the most frequent failure in 2026 and the quietest. A German regional authority, a Belgian health insurance fund or a Portuguese cooperative moves to IP; the technician reconnects the phones, not the analogue fax machine tucked away at the end of the corridor. The number still exists in the internal directory, it sometimes rings, but no fax carrier answers. Typical symptoms: negotiation that starts then drops, or a transmission that completes with a blank page.

In that case there's no point insisting: you have to reach the department through another channel and ask explicitly whether the fax is still being checked. Our guide to why faxes fail from one country to another covers the technical reasons; above all, remember that an analogue fax behind a badly configured adapter is the equivalent of a bricked-up letterbox.

2. The number outlived the service

Many foreign organisations have stopped using fax without removing the number from their letterheads, PDF forms and contact pages. In Spain, the requirement for public bodies to go through their registro electrónico (electronic register) has emptied thousands of numbers of any real use; in Italy, the spread of PEC and then the domicilio digitale (digital domicile) had the same effect. You then get a perfectly positive report: the fax was received… by a machine nobody empties.

The warning sign: a recent form that lists a fax number alongside an online portal, or a fax number identical to the main phone number. When in doubt, treat fax as a backup channel, not the main one — which is exactly the conclusion of our pages on Spain and Italy.

3. The outage is real, local and temporary

That happens too. A storm over Hainaut, civil engineering work in Porto, a fire in an exchange, a prolonged power cut in a Canadian region: the local loop goes down for a few hours or a few days, and the whole neighbourhood loses voice along with fax. Two clues: several numbers with the same area code fail, and the recipient's website or social media mentions a disruption. In Belgium, Proximus publishes a network status page; in Canada, the major operators and sometimes the municipalities report major outages.

Plan B, country by country

A plan B isn't "I'll send an email and cross my fingers". It's the channel the recipient officially recognises, that leaves you a record, and that you can cite in a follow-up letter.

Two remarks apply to that whole right-hand column. First, a record is only worth something if you keep it: export the receipt as a PDF, not as a blurry screenshot. Second, none of these channels is open to everyone: Italian PEC requires a certified address, beA is restricted to German legal professionals, a Canadian portal demands a verified identity. That is precisely why fax remains useful on the foreign sender's side — it requires no account with the recipient.

For Canadian procedures in particular, our articles on faxing a document to Ottawa and on faxing in Quebec list the services that still publish a fax number and those that now swear by their portal alone.

Preparing for the outage before it happens

The real issue isn't the outage, it's the deadline it threatens: a pension file, a missing document for a permit, an insurance claim, a response to a tender. Three habits cut the risk to almost nothing.

• Back up the number with a human contact. Before an important transmission, get an email address and a voice number for the receiving department. A single call will tell you whether the fax machine is being checked.
• Keep the document ready for two channels. A clean, legible PDF under a few megabytes, plus a signed paper version. A portable sheet-fed scanner produces crisp pages from already-folded originals in a few minutes; failing that, a smartphone steadied on a small desk tripod gives a far better result than a handheld photo.
• Send at the right time. Time slots matter more than you'd think: a Canadian fax machine swamped at the end of the Eastern working day, a European department that switches its machines off overnight. Our guide to faxing across time zones gives the useful windows between Quebec and Europe.

For repeat sendings, an expanding file folder with one divider per country — number in international format, backup channel, voice contact, last successful attempt — saves a considerable amount of time on the day everything jams. And if your documents go out from a home office, a small backup UPS for the router keeps you from losing a transmission in progress to the first micro power cut.

What counts as proof when nothing gets through

A missed deadline is easier to defend with a file of attempts than with a verbal explanation. Always put together:

1. The transmission report for each attempt, even failed ones, with date, time and the exact wording.
2. The record of your voice test: date, time, what you heard.
3. A screenshot of the source of the number (contact page, official form) as it stood on the date of sending — it shows you used the published number.
4. The submission through the backup channel, with its timestamped receipt.
5. A brief follow-up letter setting out the chronology and recalling the date of the first attempt.

On the value of these elements and their limits, see fax as proof and the fax transmission receipt. None of this creates any magic right, but before a foreign administration a documented chronology has often got a late document accepted.

Frequently asked questions

My fax worked last week and doesn't today: what changed?

In the vast majority of cases, nothing at your end. A number that worked and no longer answers points either to a line migration at the recipient's end, or to the shutdown of their fax service, or to a local outage. Test the number with a voice call: it's the fastest and cheapest diagnosis.

Should I change online fax services after several failures to the same country?

Not before testing another number in the same country. If a second recipient receives without trouble, your service works and the problem is at the receiving end. If every number in a country fails, a routing issue becomes a credible hypothesis.

Does a failed fax extend my administrative deadline?

No, not in itself. What helps is proof of attempt within the deadline, backed up by a submission through a backup channel as soon as possible. The rules vary by organisation and country: never count on automatic leniency.

Does T.38 fix international failures?

It reduces them on the sender's side when it is properly supported end to end, which is rarely guaranteed on an international transit route. It can do nothing about an unplugged fax machine at the destination. The subject is covered in detail in Fax over VoIP: why T.38 fails.

Should I tell the recipient their fax no longer answers?

Yes, and it's often useful for everyone. Many departments only discover through an outside call that their fax machine has not been receiving for weeks. Mention the times of your attempts: that lets them trace them with their operator.

Key takeaways

• A cross-border fax that suddenly fails almost always has its cause in the destination country, not at the sender's end.
• The wording of the failure report distinguishes a bad number format, a dead line and a transit problem.
• The voice call test is the fastest diagnosis: modem tone, human voice or silence — three different conclusions.
• Every country has its official backup channel: eBox, beA and KIM, registro electrónico (electronic register), PEC and domicilio digitale (digital domicile), ePortugal, the Canadian portals.
• A timestamped file of attempts is worth more than an explanation: transmission reports, voice test, source of the number, backup channel receipt.
• Prepare for the outage in advance: a human contact, a PDF ready to go, the right time window, a sheet for each country.

Need to try straight away to one of the seven destinations served? The sending form is on the home page, and questions about limits, formats and delivery times are gathered in the FAQ.