Luxembourg +352 codes: choosing the right OTP Route product

One-time code or long-term line: what does a Luxembourg project need?

Start with the question that decides everything else: will the account need the same number again?

• One verification, then done. A sign-up test, a localisation check, a fresh staging account. The OTP Gateway fits: you get a +352 number for a single code, a 20-minute window, and no charge unless the SMS lands.
• The account must log in again next month. That calls for a number you keep. Our Dedicated Numbers cover the United States and Canada only, from $1.95/month, so for a lasting Luxembourg line you would email [email protected]. Availability depends on local rules and cannot be promised.

If a test account only needs to exist long enough to exercise the flow, the gateway is simpler and cheaper. Our article on temporary vs dedicated numbers compares both options in more depth.

Which services can verify against a +352 number?

The live list for Luxembourg runs to more than 1,400 services. Teams most often reach for WhatsApp, LinkedIn, Microsoft & Outlook, Amazon, Google (Gmail & YouTube), Telegram, Signal, Uber, Airbnb, Netflix, Claude and ChatGPT (OpenAI).

That list is a snapshot. Inventory moves during the day, which is why the API answers with what is available right now rather than a fixed catalog.

How does the Luxembourg OTP API flow run?

Authenticate with a Bearer key (prefix or_live_) from the Developer console against https://otproute.com/api/v1. The flow:

1. Check GET /api/v1/countries for lu and GET /api/v1/services for your target.
2. Read the live cost with GET /api/v1/prices?country=lu&service=<id>.
3. Create the activation: POST /api/v1/activations with {"service": "linkedin", "country": "lu"}.
4. Collect the code by polling GET /api/v1/activations/{id}, or receive activation.sms_received on a signed webhook.
5. Cancel with POST /api/v1/activations/{id}/cancel if the test is abandoned.

Webhook calls carry X-OTPRoute-Signature: t=<unix>,v1=<hex>; verify the HMAC-SHA256 of <t>.<raw body> with your endpoint secret and drop old timestamps. Key your handler on the activation id so retried deliveries are harmless. Limits worth knowing: 10 keys, 5 webhook endpoints and 300 requests per minute per account. See the API integration guide for code samples.

Prefer clicking? In the dashboard, pick Luxembourg and a service, confirm the price, copy the +352 number into the app, and watch the code appear on the same screen.

How should +352 numbers be formatted and validated?

Luxembourg has no trunk prefix, so there is nothing to strip when converting to E.164: it is +352 followed by the national digits. The catch is length. Landline numbers in Luxembourg vary in length, while mobile numbers are nine digits and usually begin with 6.

For validation, that means:

• Avoid a fixed-length rule for the whole country; accept the range and lean on a maintained phone library.
• Normalise to E.164 before storage and comparison so +352 621… and 00352621… match.
• Include at least one mobile and one shorter fixed-line example in your fixtures.

Why test sign-ups for the Luxembourg market?

Luxembourg is small but unusually demanding for product teams. Luxembourgish, French and German are all official, and English is common at work, so a single user base may expect four interface languages. Verification SMS text follows the app's locale, which makes Luxembourg a compact place to test every template you ship.

It is also a European financial centre with a large cross-border workforce from France, Belgium and Germany. Users may hold a +352 number while their address sits in a neighbouring country, a mismatch that onboarding and risk rules must handle gracefully. Teams building regulated sign-ups can read our notes on fintech onboarding.

What should I do when no SMS reaches the +352 number?

• Leave the activation open for its full 20 minutes before concluding anything.
• Confirm the service accepts virtual numbers; some refuse them by policy.
• Retry later or try another service for the same test, rather than firing new orders back to back.
• Inspect your webhook logs for signature failures that might hide a delivered code.

When the window expires or you cancel, the full amount returns to your wallet on its own.

How do the wallet and sandbox work?

OTP Route runs on a single prepaid USD wallet: pay as you go, with no monthly fee and no plan tiers. Fund it by card or with USDT/USDC; every top-up arrives with a PDF invoice by email. Current rates are on the pricing page.

While you are still wiring up the +352 integration, ask us to flip your development account into sandbox mode. It hands back simulated numbers and codes so the whole flow, webhooks included, can be exercised without wallet spend.

Frequently asked questions

Can I get a Luxembourg verification number for testing?

Yes. The OTP Gateway issues a +352 number for one code, which you can read in the dashboard or receive through the API.

What country id does Luxembourg use in the API?

It is lu, used in POST /api/v1/activations and the prices endpoint.

Can I buy a permanent Luxembourg number?

Not self-serve. Dedicated Numbers are sold only for the US and Canada; email [email protected] to ask about Luxembourg.

Which languages might a Luxembourg OTP message use?

It depends on the app's language setting, so French, German, English or occasionally Luxembourgish are all plausible.

Is a refund automatic if the code is missing?

Yes. No SMS before the 20-minute window ends, or a cancellation, sends the full amount back to the wallet.

Does Luxembourg use a leading zero in phone numbers?

No. There is no trunk prefix, so numbers convert straight to +352 plus the national digits.

Are there rules on how I use these numbers?

Yes. Respect each service's terms and the OTP Route Acceptable Use Policy, and use numbers only for your own legitimate products and accounts.

Service names are trademarks of their respective owners. OTP Route is not affiliated with them. Use numbers lawfully, follow each service's terms and our Acceptable Use Policy.