Submitting a business number port correctly is less about the paperwork and more about the prep work that prevents rejection. This step-by-step guide covers the full LNP process for MSPs, IT providers, and telecom resellers: how to request a CSR, complete a Letter of Authorization that matches the losing carrier's records exactly, and avoid the BTN mismatches and address errors that send most port requests back to square one. You'll also get a plain-language breakdown of the FCC rules that govern local number portability, including the one-business-day simple port interval and the anti-slamming protections that back every valid LOA. If you're submitting ports on behalf of business customers, the second half of this guide covers how a platform like Viirtue's ViiBE turns a brittle manual porting workflow into a branded, self-service, automated process that protects your margin and your customer relationships.