What does a bad phone number cost?
A failed dial can also consume the time used to review the record, place the call, log the outcome, and schedule follow-up. Estimate that impact from sampled attempts in your own workflow rather than assuming one universal duration.
There's a second spend that's easier to miss. Carrier analytics engines watch outbound calling patterns, and a dialer that hits a high rate of invalid and disconnected numbers looks like a spam operation. That reputation follows your caller ID. Teams that dial dirty lists eventually find their legitimate calls tagged "Spam Likely" on the prospect's screen, and connect rates fall off a cliff from there.
Phone validation deals with both problems before the first dial. Send us your list, and we check each number against carrier data so your team spends its time on numbers that can answer.
What do we check on each number?
- Format and range validation. Is the number structurally valid for its country, with a real area code and an exchange that's been assigned to a carrier? Numbers in unassigned ranges can't ring anything.
- Active status. Carrier records show whether the number is in service or disconnected. Disconnected numbers come flagged so you can suppress or re-source them.
- Line type. Mobile, landline, fixed VoIP, non-fixed VoIP, or toll-free. Each behaves differently for outreach and compliance.
- Carrier of record. Which telecom serves the number today, including numbers that ported between carriers. Portability broke the old trick of inferring line type from the area code and prefix; only current carrier data gets it right.
- Federal Do-Not-Call status. Whether the number appears on the FTC's DNC registry, so your team knows which records carry restrictions before building a call list.
Why does line type change how you reach out?
Mobile numbers require special care. The FCC's consumer guide to robocalls and robotexts explains that consent requirements can depend on the technology, purpose, and number called. We flag line type and risk indicators. Your counsel should decide how those facts apply to a campaign.
Landlines. Preserve line type, validation status, consent, and suppression fields separately. For US calling and texting, map the campaign controls to the FCC telemarketing and robocall guidance.
Fixed VoIP numbers are tied to a physical service address, think office phone systems. They behave like business landlines for outreach purposes.
Non-fixed VoIP numbers (Google Voice and similar) have no physical address requirement and are the easiest type to obtain anonymously. A B2B list heavy on non-fixed VoIP usually has a sourcing problem upstream.
Toll-free numbers are main lines and support queues. They connect you to a phone tree, and no SDR sequence should waste dials on them.
What about reassigned numbers?
Carriers recycle numbers. The FCC's Reassigned Numbers Database order cites about 35 million numbers disconnected each year. That figure measures disconnections rather than confirmed one-for-one reassignments. A number previously used by a prospect can later reach a different subscriber.
A number may be structurally valid yet no longer belong to the person in the CRM. Preserve the validation date, source, line status, and uncertainty. For texts or automated calls, review the actual outreach plan with counsel and use the FCC Reassigned Numbers Database materials where relevant.
Keep ownership or reassignment questions separate from formatting and reachability results. A normalized number, a connected line, and a verified association answer different questions. Return each status independently so the team can apply its approved channel and review rules without turning one successful check into a broader conclusion.
What lands in your file?
One row per number, appended to your original record so nothing needs re-matching:
- Validation status. Valid, invalid, disconnected, or unknown.
- Line type. Mobile, landline, fixed VoIP, non-fixed VoIP, toll-free.
- Carrier. The provider currently serving the number.
- Risk flags. DNC registry presence, suspected reassignment, and anything that needs a human decision before dialing.
Records import straight back into Salesforce, HubSpot, or whatever runs your call lists. If your file mixes phones with emails and addresses, we can run the whole record through our batch validation stack in one pass.
How does the process work?
Step 1: Send the file. CSV, Excel, CRM export, any format. Numbers with extensions, country codes, or creative punctuation get normalized on our side.
Step 2: We run the checks. Each number goes against carrier and telecom infrastructure data. No call or text is placed. The phone's owner sees nothing.
Step 3: Human review of edge cases. Automated lookups disagree sometimes, especially on recently ported numbers. A person reviews the conflicts instead of letting them pass through as "unknown."
Step 4: You get the file back.
What does it cost?
Phone-validation pricing depends on eligible records, requested checks, exception handling, and delivery format. Verum provides a written, scope-specific quote and schedule after reviewing those inputs.
Compare the written project proposal with the observed time spent on failed dials in your own sample. See how Verum scopes pricing.
What belongs in the delivery file?
Keep the submitted number, normalized number, country, line type, validation status, reason code, check date, and recommended disposition in separate fields. Consent and suppression data should remain independent from technical reachability so a later campaign decision does not erase either form of evidence.
Common Questions
What does phone validation check?
Four things per number: whether it's a validly formatted number in an assigned range, whether carrier records show it as active or disconnected, what line type it is (mobile, landline, fixed VoIP, non-fixed VoIP, or toll-free), and which carrier currently serves it, including numbers that ported between carriers.
Can you tell if a number is a cell phone?
Yes. Line type comes back on each record: mobile, landline, fixed VoIP, non-fixed VoIP, or toll-free. We resolve it against current carrier data rather than the original number block, so numbers that ported from landline to mobile (or the reverse) get classified by what they are today.
Do you call the numbers to test them?
No. Validation runs against carrier and telecom infrastructure data. No call or text is placed, and the person who owns the number sees nothing.
How does phone validation help with TCPA compliance?
For US calling and texting, preserve consent and suppression records and map the campaign controls to the FCC telemarketing and robocall guidance.
What is a reassigned number and why does it matter?
Carriers can recycle disconnected numbers to new subscribers. A number that once belonged to a prospect may later reach someone else, so preserve the disconnect or reassignment source and check date. Campaign review still depends on the call method and recorded channel permission.
What about international phone numbers?
US and Canadian numbers get full coverage: status, line type, carrier, and DNC. International numbers can be validated for format, country, and line type, though carrier-level detail varies by country. Tell us the mix in your file and we'll scope what's checkable.
Stop Wasting Dials
Your reps' time goes to conversations or it goes to dead numbers. Validate the list once, suppress what's dead, and each dial after that has a chance of connecting.
Related: Email Validation | Business Status Validation | CRM Hygiene | All Validation Services