The international
calling guide

Most of what is written about cheap international calling is a list of apps. The list is the least useful part, because the apps change every year and the mechanics do not. Four properties decide what a year of calling costs you, and once you can read them off a pricing page you can evaluate any service in about thirty seconds.

The first is whether the service reaches ordinary phone numbers at all. This is the largest divide in the market and the one most comparison articles blur. WhatsApp, Signal, Telegram, FaceTime and Discord carry voice between people who installed the same application. Skype, Viber Out, Rebtel, Talk360 and Telvio connect to the public telephone network, which means the person you call needs nothing — no app, no internet, no smartphone. If the person you need to reach is a landline in a village, only the second group exists.

The second is the billing increment. A provider that bills per minute charges a whole minute for every minute started, so a forty-seven second call costs a full minute — twenty-eight per cent more than the time you spent talking. Across a month of short calls that is a much larger effect than the difference between two headline rates. A provider that does not state its increment is billing per minute.

The third is the connection fee: a flat charge added to each call regardless of length. Historically standard on calling cards and still present on some services at around five cents. On a one-minute call, a five-cent fee can double the cost.

The fourth is expiry. Several large services expire unused credit after 180 days, and some deduct a monthly maintenance charge from a dormant balance. Money you paid and cannot spend is the highest per-minute rate there is.

Every rate quoted for Telvio comes from our own published tariff, rendered from a single source file at build time, so an article and the product cannot disagree. Every rate quoted for anybody else is theirs, labelled as theirs, and omitted rather than estimated where they do not publish one.

Country codes, exit codes and area codes come from published national numbering plans. They change occasionally, and a change we have not caught is a mistake worth reporting rather than a judgement call — write to us and the page is corrected in place.

Articles carry a visible publication date and a named author, and the date moves when the content moves rather than for the sake of looking fresh. Where an article recommends Telvio it also says what Telvio does not do, because a recommendation that never mentions a limitation is an advertisement, and readers can tell.

Work out which of the four properties above actually binds for you. If your calls are short — a check-in, a confirmation, a two-minute update — the billing increment dominates and per-second billing is worth more than a lower headline rate. If your calls are long, the headline rate dominates and the increment barely matters.

If you are still calling on carrier roaming, none of this is the important decision. Roaming at one to three dollars a minute against a few cents on any VoIP service is a gap so large that which service you switch to is nearly irrelevant next to switching at all.

And if the person you need to reach does not have a smartphone, the entire free-app half of the market is unavailable to you regardless of what its ratings say. That single fact narrows the choice more than any comparison table.