Before you launch your next SMS campaign, list cleaning should be the first step in your workflow. A clean contact list for SMS means every number on your list is valid, active, and capable of receiving text messages — removing the dead weight of disconnected numbers, landlines, and duplicates that drain your budget. SMS campaign list cleaning is not optional; it directly determines your delivery rates, sender reputation, and return on every message sent.
Why It Matters
Skipping list cleaning creates several problems:
- Wasted budget — SMS platforms charge per message, including undelivered ones
- Low deliverability — Bad numbers harm your performance metrics
- Damaged sender reputation — Repeated failures can trigger throttling or filtering
- Compliance risks — Messaging numbers without valid consent or capability creates legal exposure
Data quality directly impacts ROI — cleaner lists yield higher delivery rates and lower costs per result.
How to Clean Your List in 3 Steps
1. Validate Each Number
Use a phone validation API to run real-time carrier lookups revealing whether numbers are active, their line type (mobile/landline/VoIP), current carrier, and recent deactivation or porting status. CheckThatPhone’s API returns all of these fields in a single call, making it straightforward to process lists in bulk.
2. Filter and Tag
Remove invalid, deactivated, landline, or VoIP numbers based on results. Tag numbers by risk level, channel compatibility, or region for improved segmentation.
3. Format and Deduplicate
Standardize all numbers (E.164 format for most SMS platforms), remove duplicates, and eliminate opt-outs for compliance and efficiency.
Pro Tip: Don’t Rely on Area Codes
Area codes cannot reliably indicate location or line type — mobile numbers are frequently ported or suspended. Real-time telecom data queries are essential for accurate information.
Getting Started with List Cleaning
Cleaned contact lists improve key metrics: higher delivery and open rates, more clicks, replies, and conversions, lower acquisition costs, fewer carrier rejections, and better audience targeting by channel and region. CheckThatPhone helps you clean your contact list before every SMS campaign by validating numbers against real-time carrier data — explore the API documentation to see how to integrate list validation, or view pricing plans to get started at the volume that works for you.