International SMS: what a US business needs to know before texting abroad

Texting a non-US number is a different job from texting a US number. Each country sets its own rules for who can send, from what kind of sender, at what price and with what consent. International SMS is not "US texting with a different country code." The US setup you already have, such as 10DLC registration, TCPA habits and a single per-segment rate, mostly stops at the border.

This post covers what changes when you text abroad: sender rules, alphanumeric sender IDs, pricing that varies by country and consent laws. It also covers when a US-focused platform is the right tool and when it isn't. We make Ready, a texting platform and API built for US business messaging, so we'll say plainly where it fits and where a global provider is the better choice.

How texting internationally differs from texting in the US

In the US, business texting runs on a fairly standard model. You register a brand and a campaign with the carriers (A2P 10DLC), send from local 10-digit numbers and pay per segment. If you want a refresher, our 10DLC rules and requirements post covers what carriers actually check.

Outside the US, almost every part of that model changes from country to country.

Who is allowed to send

Some countries let almost anyone send from almost any sender. Others require you to register your sender identity, and sometimes your message templates, with a national authority or with the local carriers before the first text goes out. India's DLT system is a well-known example: sender headers and templates are registered ahead of time, and unregistered traffic gets blocked.

Your US 10DLC registration does nothing for you in those countries. It is a US carrier system.

What the message shows as the sender

US recipients see a phone number. In many other countries, recipients see a business name instead. That is the alphanumeric sender ID, covered next.

What a reply looks like

If your sender is a name rather than a number, the recipient usually can't reply to it. That one detail decides whether a country can support two-way conversations at all.

Alphanumeric sender IDs, registration and why 10DLC stops at the border

An alphanumeric sender ID is a short text label, such as "ACMEDENTAL", that appears in place of a phone number. It is common for one-way traffic like delivery alerts and one-time passcodes in many markets, including the UK and much of Europe.

Here is what matters for a US business:

• They don't work in the US. US carriers expect a phone number (a 10DLC number, toll-free number or short code). A US-only texting setup has no use for them.
• They are usually one-way. Nobody can text "ACMEDENTAL" back. If you want replies, you need a number in that country, or a number type the country accepts for two-way traffic.
• Some countries require pre-registration. The name may have to be approved before you use it, and approval times vary by country.
• Some countries don't allow them at all. Others replace an unregistered name with a generic numeric sender, which looks like spam to the recipient.

The practical takeaway: you set up sender identity country by country. A provider that is serious about international SMS will publish a per-country capability sheet covering sender types, two-way support, registration needs and any content restrictions. If a provider can't show you that sheet for the countries on your list, treat that as your answer.

Pricing for international SMS: why there is no single rate

US pricing is easy to reason about. On Ready's Standard rate, every segment costs $0.0075, plus a $0.0045 carrier fee. That all-in rate excludes the optional compliance surcharge: scrubbing and landline validation are each $0.003 extra per segment when switched on, and both are off by default. Our 10DLC cost breakdown walks through the registration fees on top of that.

International pricing doesn't work like that. Rates are set per destination country, and sometimes per carrier within a country. They can differ widely between neighboring countries. Local carriers can also add their own fees for sender registration or for certain traffic types. We won't quote other providers' international rates here because they change often. Pull the current per-country rate card from whatever provider you evaluate, and check it again before a large send.

Segments still drive the bill, and language matters more abroad

Segment math is the same everywhere, but international traffic triggers the expensive case more often:

• A GSM-7 message fits 160 characters in one segment, or 153 per segment once it splits.
• Any character outside GSM-7 switches the whole message to unicode: 70 characters in one segment, 67 per segment when split.

Many non-English messages fall into unicode automatically. Arabic, Hindi, Chinese, Japanese, Korean, Thai and Russian scripts are all non-GSM. Even Spanish can trip it: "é" and "ñ" are in GSM-7, but "á", "í", "ó" and "ú" are not.

Worked example (assumptions stated): Take a 140-character Spanish appointment reminder.

• Without any accented characters, it is 1 segment.
• With one "á", it becomes unicode: 140 ÷ 67 = 2.09, so it bills as 3 segments.

That is 3x the segments for the same reminder. Whatever the per-country rate is, multiply it by 3. For comparison, the same 3-segment message sent to 5,000 US contacts on Ready Standard costs 5,000 × 3 × $0.0075 = $113, plus 15,000 × $0.0045 in carrier fees. The arithmetic is identical abroad. The per-segment rate is the part that changes.

Consent laws travel with the recipient

US senders tend to think in TCPA terms: prior express consent, quiet hours, STOP handling, and exposure of roughly $500 to $1,500 per text when it goes wrong. Abroad, the recipient's local law generally applies to you, and it can be stricter:

• Canada's CASL requires consent for commercial electronic messages, and has its own rules on identifying the sender and including an unsubscribe method.
• The EU and UK (GDPR, plus local marketing rules) set high bars for what counts as valid consent, and give people rights over their data, including the right to have it deleted.
• Many countries regulate sending hours, sometimes more strictly than US quiet-hours practice, and set them by local time.

Three practical consequences follow:

1. Your US scrubbing doesn't cover foreign numbers. TCPA-litigator and US Do Not Call lists are US lists. A scrub that's useful for your US list says nothing about a German mobile number.
2. Your consent records need to hold up locally. Keep the opt-in wording, timestamp and source in your own system, per contact. Your texting platform's send logs are not a substitute.
3. Get local legal advice before marketing abroad. This is the sender's responsibility in every country. No platform removes it.

Choosing an international SMS gateway or SMS API

If you do need to text internationally, you're shopping for an international SMS gateway or an SMS API with international coverage. That usually means one of the global CPaaS providers (Twilio, Telnyx, Plivo and similar). Here is what to check before you sign:

1. Country coverage sheet: sender types per country, two-way support and registration requirements.
2. Sender ID registration help: whether they file it for you or hand you a form and wish you luck.
3. Per-country pricing: published and current, including any carrier surcharges.
4. Delivery receipts per country: some networks report delivery poorly, so ask what you'll actually see.
5. Content rules: some countries block certain categories or require templates.
6. E.164 handling: the API should insist on full international numbers (+44..., +52...) so nothing gets misrouted.

On that last point: if you store contacts without a country code, a 10-digit number is easy to misread as a US number. Ready's messaging API treats a 10-digit number as +1, which is right for US lists and exactly why you should store everything in E.164 from the start.

When a US-focused platform is the right fit (and when it isn't)

Ready is a business texting platform for the United States, Canada, the United Kingdom and Australia. Its compliance stack starts from US rules: in-app 10DLC brand and campaign registration (most approvals take 2 to 7 days), automatic STOP handling, quiet hours based on the recipient's area, and TCPA-litigator and DNC scrubbing. Each country has its own sender rule (a US contact gets texts from a US number, for example), and Ready does not send to other countries. If your list mixes countries, talk to us before assuming any coverage. Texts to Canada, the United Kingdom and Australia can add a country carrier fee for each segment, shown on its own line of your bill.

A global CPaaS is also priced at or below Ready per segment in the US (Twilio is around $0.0083/segment). So if you have engineering time and a multi-country roadmap, building on one is a reasonable choice. Teams pick Ready for something else: US registration handled in-app, STOP handling and quiet-hours holds on for every account, and an inbox, campaigns and automations included instead of built from scratch. If you're weighing a non-US provider for US traffic, our Burst SMS alternative post covers that situation.

Practical setup if most of your list is in the US

If you're a US business with a mostly US audience and a handful of overseas contacts, here's a sensible order of work:

1. Normalize every number to E.164 and tag each contact's country.
2. Split the list by country. Send US contacts through your registered US setup. Route the rest separately, or reach them by email.
3. Validate the US side. A number lookup such as GET /v1/validate/:phone (number validation docs) catches landlines before you pay for a failed send.
4. Scrub the US side if you're in a higher-risk vertical. The standalone TCPA and DNC litigator scrub is $0.005 per contact.
5. Write once, check segments twice. Translated copy often becomes unicode, so count segments before you approve the send.

The practical takeaway

International SMS is a country-by-country exercise. Sender IDs, registration, pricing and consent all vary, and your US setup doesn't carry over. If texting abroad is central to your business, choose a global gateway with a real coverage sheet. If your audience is overwhelmingly American, a US-focused platform does that job well. You can try Ready by signing up. The first 20 texts are free one-to-one sends, so use them to test your US flow before you register.

FAQ

What is international SMS? It is any text sent to a phone number outside your own country. For a US business, that means any number without a +1 US prefix. It follows the destination country's sender, pricing and consent rules.

How do I text internationally from a US business? Use a provider with coverage in the destination country. Set up the sender type that country accepts (a local number or a registered alphanumeric ID), store numbers in E.164 format and confirm that your consent meets local law.

Does 10DLC registration work for international SMS? No. A2P 10DLC is a US carrier registration system. Other countries have their own sender registration schemes, and some have none.

Why does international SMS cost more and vary so much? Rates are set per destination country and carrier. Many non-English messages also switch to unicode, which cuts a segment to 70 characters and multiplies the segment count.

Can Ready send international SMS? Ready serves businesses in the United States, Canada, the United Kingdom and Australia texting contacts in those countries. It is not built for sending to other countries, so if your list includes numbers from anywhere else, talk to us first. If multi-country sending is core to your product, a global SMS API is the better fit.