How do I cut the cost of calling our overseas suppliers?

This page may contain affiliate links from which Blur Studio earns commissions.

International calling costs on a standard mobile plan are one of those expenses that creeps up slowly enough that nobody flags it until someone actually opens the bill. Mobile carriers price international and roaming calls at a steep premium specifically because they can, most customers never shop around for a better route, they just pay it.

One direct fix worth knowing about upfront is routing these calls through a VoIP business phone system, such as KrispCall, instead of dialing straight out through your mobile carrier. It is one option among a few, alongside free app calls for suppliers willing to use them and local virtual numbers for the reverse direction, and which one actually makes sense depends on your real call volume, which is exactly what the rest of this guide walks through.

Why the bill is so high in the first place

A standard mobile plan is built around domestic calling. International calls, and especially calls made while roaming abroad, get priced on a completely different, much higher rate card, often per minute with no bundled allowance. If your agents are dialing international supplier numbers directly from their phone's normal dialer using their regular carrier plan, you're paying the single most expensive route available for that call, by design, not by accident. If staff are the ones roaming, see getting office calls while you travel.

The real alternatives, in order of effort

Start with the free option before paying for anything. If a supplier is willing to take calls over an app like WhatsApp, and plenty of suppliers in markets where WhatsApp is standard business practice are, that call costs nothing beyond your existing data plan. This isn't always appropriate for formal business communication, but for a quick check-in with a supplier you already have a relationship with, it's genuinely free and instant.

Where WhatsApp isn't a fit, a VoIP business phone system like KrispCall routes calls over the internet rather than through your mobile carrier's international rate card, which is typically priced per minute by destination country and usually comes in well under standard mobile roaming or international rates. I can't give you an exact per-minute figure for every country here since KrispCall's specific international rate card by destination wasn't something I could independently verify on a page reachable directly, which is exactly why the next section matters more than any single number I could quote you.

A third option, covered in more depth in my guide to getting a local number abroad, is buying a local virtual number in the supplier's country. This mainly helps when the supplier is calling you, since it removes their international cost, but it's less directly relevant when you're the one making the outbound call to them.

Step by step: how to actually fix this

1. Add up last quarter's actual international minutes and spend, by country if your carrier's billing lets you break it down. Most teams skip this step and switch tools based on a guess rather than a real number, which makes it impossible to know afterward whether anything actually improved.
2. Get real rate quotes for your top two or three supplier countries specifically, from a VoIP provider, rather than trusting a generic "cheap international calls" marketing claim. Rates genuinely vary by destination country, sometimes a lot.
3. Run a handful of real test calls on the new route before switching your whole team over, and check call quality as well as cost, since a cheap route that drops calls or has bad audio quality isn't actually a saving once you count the wasted callbacks.
4. Switch your highest-volume supplier routes first, not everything at once, so you can see the actual before-and-after on your bill rather than one big change you can't attribute.

What I'd actually tell you

The single biggest mistake I see on this specific problem isn't picking the wrong tool, it's never establishing the baseline number in the first place. A business that switches to VoIP without knowing what it was actually spending before has no way to know if the switch worked, and I've seen teams "save money" on paper while actually increasing total spend because they added a monthly subscription on top of calls they'd have made for free anyway through an app the supplier was happy to use. Do the boring arithmetic first. A shorter version of this advice is in calling suppliers abroad without a huge phone bill.

Second honest point: if your call volume with overseas suppliers is genuinely low, a handful of calls a month, the subscription cost of a dedicated VoIP seat can outweigh what you'd save on the calls themselves. In that case, free app calls for the suppliers who'll use them, plus accepting the occasional real carrier charge for the rest, is often the actually cheaper answer, even though it feels less "solved."

A worked example: a distributor calling three countries

Say a small import distributor calls suppliers in three countries regularly: a steady weekly call to a manufacturer in Vietnam, occasional calls to a supplier in Turkey, and rare calls to a third supplier in Brazil. Pulling the actual carrier bill shows the Vietnam calls alone account for most of the international spend, simply because they happen weekly rather than occasionally. That's the obvious place to start: get a real VoIP rate quote specifically for calls to Vietnam, test it on a handful of real calls, and compare the actual bill the following month against the baseline already established. The Turkey and Brazil routes, called rarely enough that the subscription math doesn't clearly favor switching yet, can stay on the existing carrier plan or move to a free app call if the supplier's willing, revisited once volume to either country grows enough to matter.

Common mistakes to avoid

• Switching every supplier relationship to the new route at once. Moving your highest-volume route first and watching the real before-and-after number tells you whether the switch actually worked; moving everything simultaneously makes it much harder to tell which change, if any, produced the saving.
• Ignoring call quality in the cost comparison. A noticeably cheaper per-minute rate that results in dropped calls or poor audio quality on an important supplier negotiation isn't actually a saving once you count the wasted time and the awkwardness of a call that has to be redone.
• Assuming a flat percentage saving applies to every country equally. VoIP rates vary meaningfully by destination; a saving that's dramatic for calls to one country can be minor for another, which is exactly why getting country-specific quotes matters more than trusting a single average figure.

When to skip this, and when it's worth more

Skip switching tools entirely if your real international call volume is small and infrequent; the fix there is behavioral (use a free app where you can) not a new subscription. This is worth a real setup once you have multiple people regularly calling several countries, where the per-minute savings across the team actually add up to more than the seat cost.

How I'd approach this

If you're past the point of manually tracking who calls which country on what app, and want call costs, call logs and supplier contact data all living in one system your team already uses, that's worth building properly on top of a VoIP provider's API rather than managing it by hand across several tools. I build that kind of integration for clients who've outgrown the manual version, and if a half-finished setup from a previous attempt is part of the problem, sorting that out first is usually the faster path.