Frequently Asked Questions
Everything you need to know about receiving SMS verification codes with SMSTwins — from privacy and pricing to API integration and refunds.
What is a virtual phone number for SMS verification?
A virtual phone number is a real mobile line you can use temporarily to receive SMS verification codes (OTP) during account registration or testing — without linking your personal phone number. SMSTwins supplies non-VoIP numbers from verified SIM providers for reliable delivery.
Why would I use a virtual number instead of my personal phone?
Your mobile number is a long-lived identifier tied to your identity, location, and marketing profiles. Using a dedicated verification number helps protect your privacy, reduce unwanted contact, and keep work or testing activity separate from your personal life.
Who uses SMSTwins?
Software developers validating onboarding flows, QA engineers testing international apps, freelancers managing client accounts, security researchers in controlled environments, and individuals who prefer not to publish their personal number when signing up for new services.
What happens if I do not receive a verification code?
If no SMS arrives within the activation window, your balance is refunded automatically. You can request another number and try again without opening a support ticket.
Does SMSTwins offer an API for developers?
Yes. SMSTwins provides a REST API, webhooks, and a Simple API for scripts. Documentation covers authentication, activation lifecycle, and event-driven integrations for staging and CI environments.
How do I pay for virtual numbers?
Top up your account with cryptocurrency on our secure checkout page. Credits are consumed per activation — you only pay when you request a number.
Are SMSTwins numbers real mobile numbers?
Yes. Numbers come from registered SIM providers operating physical hardware through our gateway. These are genuine mobile lines, not recycled VoIP routes.
Is SMSTwins designed for privacy?
Privacy is central to our product. Temporary numbers create a boundary between your personal identity and the services you register for — whether you are testing software, working internationally, or simply prefer a cleaner digital footprint.
Can I use SMSTwins for software testing and QA?
Absolutely. Teams use SMSTwins to exercise registration flows, password recovery, and two-factor SMS paths in development, staging, and automated test pipelines. API keys, webhooks, and rate tiers support professional workflows.
How fast do verification codes typically arrive?
Most OTP messages arrive within seconds on active routes. Delivery depends on the sending platform and mobile network conditions. Our routing prioritizes providers with strong historical success rates.
What countries and services are supported?
We cover 180+ countries and hundreds of popular platforms. Browse the Services directory and Virtual Numbers pages to explore country and service combinations, or use the dashboard to see live availability.
Do you offer number rentals or only one-time activations?
SMSTwins focuses on activation-based verification — request a number, receive your code, and complete your workflow. For extended testing needs, contact us about volume or enterprise options.
How does the provider network work?
Independent SIM suppliers connect approved gateway software to our platform. They sync inventory, receive activation assignments, and forward inbound SMS securely. Quality scoring helps route your request to reliable numbers.
What is your refund policy for failed activations?
Timed-out activations release held balance automatically. Manual cancellation during the waiting window also refunds your hold. You are not charged for activations where no verification SMS was received in time.
Can freelancers keep client work separate from personal accounts?
Many freelancers register on marketplaces, payment tools, and collaboration apps with a dedicated verification number so client-related sign-ups never expose their personal mobile line.
Is there a referral program?
Yes. Share your referral link from the dashboard. When referred users top up, you earn commission credited to your balance. See the Referrals page for current terms.
How do webhooks work?
Configure a webhook URL in your dashboard. When an activation receives SMS or changes state, SMSTwins sends a signed POST payload. Verify signatures with your webhook secret to integrate real-time events into your backend.
Where can I read about acceptable use?
Our Terms of Service describe platform rules. SMSTwins is built for verification, testing, and privacy-conscious registration — transparent policies and abuse reporting help keep the network healthy for everyone.