United Kingdom Verification Numbers: A +44 OTP Testing Checklist

Checklist: is your stack ready for +44 verification codes?

Run through this list before a release candidate hits the UK leg of your test plan:

• [ ] A Developer-console key (or_live_ prefix) scoped to the job that will use it.
• [ ] The UK country id, gb, wired into your fixtures, plus the service id from GET /api/v1/services.
• [ ] A decision on delivery: a signed webhook for parallel suites, or polling for a quick script.
• [ ] Phone-number parsing that handles the UK leading zero (more on that below).
• [ ] Enough balance, confirmed with GET /api/v1/balance, or a sandbox account for dry runs.
• [ ] A note in the runbook that one number serves exactly one code.

Teams wiring this into pipelines will find SMS OTP testing in CI pipelines a useful companion.

How does the UK OTP API flow work for the gb country id?

The sequence mirrors what a human tester does by hand, just faster and logged:

1. Price the pair with GET /api/v1/prices?country=gb&service=<id>; the response reflects live availability.
2. Reserve a number with POST /api/v1/activations and {"service": "<id>", "country": "gb"}.
3. Put the +44 number into the sign-up, login or recovery screen and request the SMS.
4. Receive the code via the activation.sms_received event or by reading GET /api/v1/activations/{id}.
5. Abort cleanly with POST /api/v1/activations/{id}/cancel when a test is skipped.

A webhook handler should treat every request as untrusted until the X-OTPRoute-Signature header checks out: HMAC-SHA256 of <t>.<raw body> with the endpoint secret must equal v1, and the timestamp must be recent. Persist results keyed on the activation id so duplicate deliveries are harmless. The limits are generous for most suites: 300 requests per minute, up to 10 keys and 5 webhook endpoints per account. Full reference is in the developer docs.

Which UK services and apps are on the route?

The United Kingdom is one of the broader routes, with more than 4,000 services available. Popular options include WhatsApp, Google (Gmail & YouTube), Amazon, Uber, Netflix, eBay, Airbnb, LinkedIn, Microsoft & Outlook, Instagram, Snapchat, X (Twitter), Discord and ChatGPT (OpenAI).

Routes change hour to hour, so let the price endpoint or the dashboard tell you what is orderable now rather than assuming yesterday's result still holds.

Handling the leading zero: storing UK mobile numbers in E.164

The UK uses a trunk prefix of 0. People write their mobile as 07xxx xxxxxx, eleven digits, but internationally the 0 disappears and the number becomes +447xxxxxxxxx. The most common bug in UK phone fields is keeping both, which produces an invalid +4407… string that no SMS gateway will deliver to.

Checks worth adding to your test suite:

• Input of 07… is normalised to +447… before it is saved.
• Input already in +44 7… form passes through unchanged.
• Spaces in the familiar 07xxx xxxxxx grouping are stripped.
• Display formatting is applied only on output, never stored.

Verification messages for British users arrive in English. Welsh is also an official language in Wales, so public-facing services with a bilingual interface may want to check that templates and screens behave in both.

Why QA and growth teams test against British numbers

For many companies the UK is either the home market or the first one outside it. Financial products in particular tend to put phone verification at the centre of onboarding and step-up checks, so a broken +44 flow shows up quickly in support queues.

Common reasons to order a +44 number for testing:

• A UK launch, where the en-GB build needs its own pass for spelling, date formats and the country picker.
• Regression tests on login and account recovery after a change to your SMS provider settings.
• Recreating a British customer's failed sign-up to see where the code went missing.

The fintech onboarding page describes how teams structure those checks.

Troubleshooting a missing +44 code

When the code doesn't arrive, avoid the instinct to re-order straight away. Instead:

1. Let the 20-minute window finish; some services hold messages briefly.
2. Read the activation status. If it ends as expired, nothing arrived and the full amount is already back in the wallet.
3. Remember that some services refuse virtual numbers. That outcome is exactly what the refund rule covers.
4. Retry after a pause, or with another route for the same service, rather than looping orders.
5. Confirm your app sent the request for an SMS at all, and that it went to the +44 number you reserved, not a stale fixture.

Dashboard path, billing and long-term UK lines

Non-developers can do all of this without code: open the dashboard, choose United Kingdom and the service, confirm the price shown, copy the number into the app and watch for the code on the same page.

There is no self-serve long-term UK number. Dedicated Numbers are a US and Canada product, from $1.95/month; for a persistent British line, email [email protected], and the team will explain what local rules permit without promising it. Everything runs on a prepaid USD wallet with no monthly fee, funded by card or USDT/USDC, with PDF invoices by email. Details are on the pricing page.

Frequently asked questions

Can I test my app's UK sign-up flow without a British SIM?

Yes. Request a +44 number from the OTP Gateway, enter it in your sign-up screen and read the code from the dashboard, a webhook or the activation endpoint.

Is the UK country id `uk` or `gb` in the API?

It is gb, following the ISO country code.

How do I convert a UK number that starts with 07?

Drop the leading 0 and prefix +44, so 07… becomes +447….

Do I pay for a UK activation that times out?

No. If no SMS arrives within 20 minutes, or you cancel, the full charge returns to your wallet automatically.

Can OTP Route give me a UK number I keep for months?

Not as a self-serve product. Long-term Dedicated Numbers are sold only for the US and Canada; you can email support to ask about the UK, with no assurance it is possible.

Can I try the UK integration in a sandbox first?

Yes. A development account can be switched to sandbox on request, returning simulated numbers and codes so you can test without spending wallet funds.

What usage rules apply to UK verification numbers?

Follow each service's terms and OTP Route's Acceptable Use Policy, and use the numbers only for your own legitimate products, tests and business 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.