Verify Phone Numbers Are Still Active
Verify Phone Numbers Are Still Active with Cleanlist's waterfall enrichment. Upload a CSV or connect your CRM — 30 free credits to start.
Start Free — 30 CreditsThe Problem
Sales development teams dial hundreds of numbers per day, but studies show that 25-40% of B2B phone numbers in the average CRM are no longer valid. Every call to a disconnected or reassigned number wastes 30-60 seconds — and across a 10-person SDR team making 60 dials each per day, that adds up to 6-10 hours of wasted time daily. Worse, repeatedly calling invalid numbers from the same caller ID can trigger carrier-level spam flags on your outbound number.
How Cleanlist Solves This
Cleanlist verifies phone numbers at three layers: carrier validation (is the number assigned and active?), line type detection (mobile, landline, VoIP, fax), and connectivity status (ring, disconnect, or carrier intercept). The result is a verified list where every number connects to a real person — not a disconnected line, fax machine, or reassigned subscriber.
Carrier-Level Spam Flagging Is the New Cold Calling Threat
Hiya's 2025 State of the Call report found that 34% of outbound B2B sales calls are now flagged with 'Spam Likely' or 'Scam Likely' labels by carrier-level call screening services (T-Mobile Scam Shield, AT&T Call Protect, Verizon Call Filter). The primary trigger is calling patterns: dialing many numbers in sequence, high rates of unanswered calls, and repeatedly calling disconnected numbers. Each of these signals is amplified when your dialing list contains invalid numbers. If 30% of your list is disconnected, every call to a dead number increases your spam probability score. Cleanlist phone verification removes disconnected numbers before they enter your dialing queue, reducing the signal that triggers carrier spam flags. SDR teams that pre-verify their phone lists report 40-60% fewer 'Spam Likely' flags on their outbound caller ID — directly increasing the percentage of calls that ring through to the prospect's phone.
Source: Hiya State of the Call Report 2025; Cleanlist customer call analytics, Q1 2026
How It Works
Upload Phone Numbers
Upload a CSV with phone numbers in any format — Cleanlist normalizes international, domestic, and mixed-format numbers automatically. Supports E.164, national, and local formats with or without country code.
Number Normalization
All numbers are parsed and formatted to E.164 international standard. Invalid formats (too few digits, non-numeric characters, impossible area codes) are flagged immediately without using verification credits.
Carrier & Line Type Detection
Each number is checked against carrier databases to determine the operator and line type: mobile (personal or company cell), landline (direct dial or switchboard), VoIP (virtual number), or fax. This helps SDR teams prioritize the most connectable numbers.
Connectivity Verification
Numbers are tested for active service status. Disconnected lines, numbers reassigned to different subscribers, and carrier-intercepted numbers (fraud blocks) are identified and flagged without making an actual call.
DNC Registry Check
Every number is screened against the Federal DNC Registry and applicable state-level lists. TCPA-restricted mobile numbers are flagged separately. Compliance status is included in the export for your records.
Export Verified Numbers
Download your verified numbers with status columns (Active, Disconnected, DNC-Restricted, Fax) and line type classification. Push directly to your dialer in the format it expects — including support for custom dialer field mapping.
Key Benefits
98% Email Accuracy
Real-time email verification catches bounces, catch-alls, and disposable addresses before they cost you.
15+ Data Providers
Waterfall enrichment across multiple providers means higher match rates than any single-source tool.
No Code Required
Upload a CSV, connect your CRM, or use the API. Works however your team prefers.
30 Free Credits
Start enriching immediately. No credit card, no sales call, no commitment.
Manual Process vs Cleanlist
| Feature | Manual | Cleanlist |
|---|---|---|
| Verification method | Dial and listen (wastes rep time) | Carrier database query + connectivity check (no calls made) |
| Line type identification | Unknown until someone answers (or doesn't) | Pre-classified: mobile, landline, VoIP, or fax |
| DNC compliance check | Manual lookup on ftc.gov (one number at a time) | Automated Federal + state DNC check for every number |
| Speed (5,000 numbers) | Would take a team weeks of dialing | Under 3 minutes (batch verification) |
| Reassigned number detection | Only discovered when wrong person answers | Carrier-level reassignment detection before you dial |
| Format standardization | Inconsistent — reps enter numbers differently | Auto-normalized to E.164 (consistent dialer import) |
Frequently Asked Questions
How accurate is Cleanlist's data?
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Cleanlist achieves 98% email accuracy through real-time verification and cross-referencing across 15+ data providers. Every record is validated before delivery.
How many free credits do I get?
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Every new account starts with 30 free credits. Each credit processes one record (enrichment, verification, or lookup). No credit card required to start.
What data providers does Cleanlist use?
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Cleanlist uses waterfall enrichment across 15+ providers including major B2B data sources. The system automatically selects the best provider for each record to maximize match rates.
Can I connect my CRM?
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Yes. Cleanlist integrates with HubSpot, Salesforce, and other CRMs. Enriched data syncs back automatically. You can also upload CSV files or use the REST API.
How long does it take to verify my data?
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Most jobs complete in under 2 minutes for up to 10,000 records. Larger files are processed in batches with progress updates.
Does phone verification actually call the number?
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No. Cleanlist verifies phone numbers through carrier database queries and connectivity checks at the network level — no calls are placed, and the number owner receives no notification. This is the same technology carriers use to route calls, applied to pre-verify your list before dialing.
How accurate is line type detection (mobile vs. landline vs. VoIP)?
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Line type detection is 95-98% accurate for numbers in the US and Canada, based on carrier records. Note that number porting (when someone moves a landline number to a mobile carrier, or vice versa) can create temporary discrepancies. Cleanlist uses real-time carrier lookups that reflect current porting status.
Can I verify international phone numbers?
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Yes. Cleanlist supports phone verification in 200+ countries. Coverage and accuracy are highest in the US, Canada, UK, Australia, Germany, and France. For other countries, carrier data availability varies — Cleanlist returns a coverage confidence indicator for each region.
Ready to verify your phone numbers?
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