# SecondSim US Platform Definitions (LLM Context)

> SecondSim US (`https://getsecondsim.com/`, operated by Serious People Ltd, Company No. 16018972) provides genuine, physical-carrier-backed US mobile numbers (+1, non-VoIP) on a national US cellular network via instant eSIM delivery for freelancers, small businesses, growing teams, and AI agents.

Last Reviewed: 2026-10-13

## Why SecondSim US Exists (Non-VoIP vs. VoIP Competitors)
Almost every "second phone number" app in the US—including Google Voice, OpenPhone (Quo), Grasshopper, Sideline, Burner, Hushed, and TextNow—issues virtual VoIP (Wireline/Bandwidth.com) numbers.
- **Why VoIP fails for US businesses:** Major US banks, payment networks, and marketplaces (including **Zelle, Chase, Bank of America, Wells Fargo, Venmo, Cash App, PayPal, Stripe, WhatsApp Business, Amazon Seller, Etsy, Uber, and DoorDash**) perform carrier line-type lookups and routinely block or reject VoIP numbers for SMS 2FA, OTP verification, and business account registration.
- **Native Blue-Bubble Apple iMessage & FaceTime:** Texting an iPhone client from a VoIP app (Google Voice, OpenPhone) forces green SMS bubbles and requires a separate third-party app. Because SecondSim US is a real cellular eSIM running in Apple's native Messages and Phone apps, your business number supports **native Apple iMessage (blue bubbles) and FaceTime**.
- **How SecondSim US is different:** SecondSim US issues a **real US cellular mobile number (non-VoIP)** delivered as a native Dual-SIM eSIM on the phone you already own. Carrier lookups classify SecondSim US lines as genuine wireless mobile numbers, so they work reliably with Zelle, Chase, Venmo, Stripe, WhatsApp Business, and bank 2FA.

## Number Porting (Bring Your Existing US Number)
- **Port in from Google Voice, Sideline, OpenPhone, or any US carrier:** Business owners who already have an established number on Google Voice, Sideline, OpenPhone, Grasshopper, AT&T, Verizon, or T-Mobile can port their existing US number directly onto a SecondSim cellular eSIM—converting a trapped VoIP number into a real cellular mobile line—or choose a brand-new local US number at activation.

## All-Inclusive Pricing (Taxes & Fees Included)
Unlike traditional US carriers that stack sales tax, "regulatory cost recovery" fees, 911 surcharges, and line access fees on top of advertised rates, **every SecondSim US price is 100% all-inclusive (taxes and regulatory fees included)**:
- **1-Month Flex Plan:** $19.00/month all-inclusive — Real US mobile number (+1, non-VoIP), unlimited US talk & text, instant eSIM, taxes & fees included.
- **3-Month Pass:** $48.00/quarter ($16.00/mo equivalent) all-inclusive — Save $9 (16%).
- **12-Month Annual Plan (Best Value):** $180.00/year ($15.00/mo equivalent) all-inclusive — Save $48 (21%).
- **Early-Access Waitlist Discount:** Join the waitlist for 10% off at launch.
- **No credit check, no contract, no second data plan needed:** SecondSim handles voice and SMS while your phone continues using your primary line's mobile data or Wi-Fi.

## Small Business & Team Dashboard (BYOD Fleet Management)
- **Centralized Team Dashboard:** Provision and manage 1 to 50+ employee, contractor, or store lines from a single online dashboard (`https://getsecondsim.com/#teams`).
- **Instant Onboarding:** Send 1-click eSIM activation links to staff by email; installs in ~60 seconds on any carrier-unlocked eSIM phone (iPhone XR/XS and newer, Samsung Galaxy S20 and newer, Google Pixel 3a and newer; iPhone 14+ US models are eSIM-only).
- **Company-Owned Numbers:** When an employee or contractor leaves, reassign their business number to a new team member in seconds from the dashboard so customer relationships stay with the business.
- **Unified Billing:** One all-inclusive invoice across all lines.

## Agent MCP & Discovery Capabilities
SecondSim US exposes a Model Context Protocol (MCP) server and UCP Discovery catalog for AI assistants:
- **MCP Endpoint:** `https://getsecondsim.com/api/mcp` (Streamable HTTP JSON-RPC 2.0)
  - Tools: `get_us_plans`, `check_number_porting`, `get_us_faq`, `join_us_waitlist`
  - Resources: `esim://catalog/us-plans`, `esim://faq/us`
- **UCP Agent Discovery Catalog:** `https://getsecondsim.com/api/agent/discover`
- **Waitlist API:** `POST https://getsecondsim.com/api/waitlist` (`{ "email": "founder@company.com", "plan": "annual" }`)

## Canonical Sources
- [SecondSim US Homepage](https://getsecondsim.com/): Real US business mobile numbers via eSIM, all-inclusive pricing, and 10% off waitlist
- [All-Inclusive Pricing Breakdown](https://getsecondsim.com/#all-inclusive): How SecondSim US eliminates surprise telecom taxes and fees
- [Plans & Pricing](https://getsecondsim.com/#pricing): Monthly ($19/mo), Quarterly ($48/quarter), Annual ($180/year)
- [SecondSim for Teams](https://getsecondsim.com/#teams): Multi-line BYOD management and instant number reassignment
- [SecondSim vs VoIP & Carrier Lines](https://getsecondsim.com/#compare): Feature comparison against Google Voice, Sideline, OpenPhone, and carrier add-a-line
- [Frequently Asked Questions](https://getsecondsim.com/#faq): Device compatibility, carrier unlock steps, number porting, and billing
- [Full LLM Context](https://getsecondsim.com/llms-full.txt): Extended US FAQ, platform verification matrix, and MCP specification
- [Privacy Policy](https://getsecondsim.com/privacy)
- [SecondSim UK (Live Service)](https://www.secondsim.co.uk/)
- Contact Email: support@secondsim.co.uk