6 Best Phone Number Lookup Tools for B2B Sales in 2026
By Kushal Magar · October 28, 2026 · 14 min read
Key Takeaway
The best phone number lookup tools for B2B sales in 2026 split by region, lookup method, and cost per number. SyncGTM ranks first for list-based calling: it queries 50+ providers in sequence, charges 10 credits per mobile ($0.16 to $0.49 depending on plan), and does not bill misses. Lusha is the fastest LinkedIn reveal for US prospects at 5 credits per phone, Kaspr is the budget European LinkedIn pick with 100 phone credits from $49 per user per month billed annually, ContactOut has the lowest per-number cost at volume with a 1,000-phone monthly fair-use cap for $79 to $99 a month, Seamless.AI pairs real-time search with calling for US teams, and Cognism leads UK and EU calling with phone-verified mobiles screened against 16 Do Not Call lists.
Phone number lookup tools take a prospect's name, company, LinkedIn URL, or email and return a number your reps can call: ideally a mobile or direct dial, not the switchboard. The best ones for B2B sales in 2026 differ on three things that decide your cost per conversation: price per verified number, coverage in the regions you call, and how they handle Do Not Call and GDPR rules.
Most roundups rank these tools by database size. That number tells you little, because a tool that returns 10,000 numbers is a bad deal if most of them ring a reception desk.
This guide compares 6 phone number lookup tools on what it costs to get a number that connects: SyncGTM, Lusha, Kaspr, ContactOut, Seamless.AI, and Cognism. Prices come from each vendor's pricing page in October 2026, in USD, and we flag every figure that comes from third parties instead.
SyncGTM is our product, so we list it first and spell out where it falls short.
Quick Summary
UK and EU calling: Cognism. One-click LinkedIn reveals in the US: Lusha. Cheapest European LinkedIn lookups: Kaspr. Lowest cost per number at volume: ContactOut. Search plus calling in one US tool: Seamless.AI. Highest find rate across a whole list: a multi-provider waterfall.
TL;DR
- SyncGTM — Best for finding numbers across a whole list. Phone waterfall across 50+ providers, mobiles at 10 credits ($0.16 to $0.49 each), and misses are not billed. From $49/mo.
- Lusha — Best for one-click LinkedIn reveals on US prospects. A phone costs 5 credits, so Starter ($49.90/mo) covers 80 numbers.
- Kaspr — Best budget pick for European LinkedIn prospecting. 100 phone credits a month from $49 per user per month billed annually.
- ContactOut — Lowest cost per number at volume. Unlimited phones under a 1,000-a-month fair-use cap for $79 to $99 a month, one user.
- Seamless.AI — Best for US teams that want search and calling in one tool. Basic is reported at about $147/mo for 250 credits.
- Cognism — Best for UK and EU calling. Phone-verified Diamond Data mobiles checked against 16 Do Not Call lists; quote-only, reported from $15,000 a year.
What a B2B Phone Number Lookup Tool Does
A B2B phone number lookup tool searches one or more contact databases for a specific person at a specific company and returns a number you can dial. It works forward, from person to number, which is the opposite of a consumer reverse lookup that tells you who just called.
The result is one of three number types, and they are not equally useful:
- Mobile. Follows the person across jobs and usually connects most often. Mobiles also carry the strictest calling rules.
- Direct dial.Rings the person's own desk line and skips the switchboard. Good for office-based buyers, less so for remote teams.
- Switchboard or HQ line. Reaches reception, not your buyer. Count these as misses when you judge a tool.
We cover the forward-versus-reverse split in our business phone number finder guide, and multi-provider setups in the best waterfall phone finders. This post focuses on the buying decision for sales calling: what each verified number costs, where coverage is strong, and how each tool fits your compliance process.
How Lookup Works: Extension, Bulk CSV, or API
Phone number lookup tools deliver numbers in three ways, and the right one depends on how your reps build call lists.
- Browser extension. A rep opens a LinkedIn profile and clicks reveal. It is fast for 20 to 50 hand-picked prospects a day, but every reveal is a manual click.
- Bulk CSV or CRM enrichment. You upload a list or select CRM records, and the tool fills in numbers for every row. This suits SDR teams loading a dialer each morning.
- API. Your own systems request numbers when a lead arrives or a signal fires. This suits RevOps teams automating routing and enrichment.
| Tool | Browser extension | Bulk CSV / CRM | API | Sends numbers to |
|---|---|---|---|---|
| SyncGTM | None; lookups run on tables | Yes, waterfall columns on any list | API, MCP server, CLI | HubSpot, Salesforce, Pipedrive, Attio, Close |
| Lusha | LinkedIn, Sales Navigator, company sites | Yes, list and CRM enrichment | Yes, on higher plans | Major CRMs and sales tools |
| Kaspr | LinkedIn profiles, groups, events; Sales Navigator from Starter; Recruiter Lite on Business | Yes, lead list enrichment | On request | CRMs plus Aircall and Ringover dialers |
| ContactOut | LinkedIn and Gmail | Yes, data enrichment | Team/API plan (quote) | Built-in cloud dialer; Salesforce on Team plan |
| Seamless.AI | Any website | Yes, list and CRM enrichment | Upper plans (reported) | Built-in engagement hub with calling |
| Cognism | Yes | CRM Enrichment add-on | Yes, shares the credit pool | Major CRMs and sales engagement tools |
Rule of thumb: if reps pick prospects one at a time on LinkedIn, buy an extension-first tool. If you call lists of hundreds, cost per number on bulk enrichment matters more than the extension.
How We Compared Each Tool
We scored each phone number lookup tool on five things a sales leader pays for:
- Cost per numberon the cheapest paid plan, from the vendor's own credit rules.
- Regional coverage, based on where each vendor focuses and what it claims.
- Compliance support, such as DNC screening and GDPR or CCPA certifications.
- Lookup method: extension, bulk enrichment, API, and dialer or CRM delivery.
- Billing on misses: whether an empty or switchboard result still costs you.
Accuracy and database figures are vendor claims unless we say otherwise; we did not run a controlled accuracy test. Where a pricing page hides numbers behind signup, we cite third-party reports or our own earlier reviews and say so.
1. SyncGTM
SyncGTM — waterfall enrichment for mobile numbers, work phones, and emails across 50+ providers
SyncGTM finds phone numbers with a waterfall: it asks one provider for a number and, if that provider misses, moves to the next, across 50+ data providers under one subscription. A mobile number costs 10 credits, a work phone costs 12, and lookups that come back empty are not billed.
On the $49 Solo plan, 1,000 credits buy 100 mobile numbers, or $0.49 each. On Business ($649/mo for 40,000 credits), the same mobile costs about $0.16.
Lookups run on lists rather than one profile at a time. You import a CSV or a lead source into a table, add a Find Mobile Number or Find Work Phone column, and push results to your CRM.
The same lookups run over the API and the enrichment MCP server for Claude. A separate Verify Mobile Numbers action (1 credit) checks numbers before they reach a dialer.
Pros
- ✓ Queries 50+ data providers in sequence under one subscription
- ✓ Lookups that find nothing are not billed
- ✓ Cost per mobile falls from $0.49 on Solo to about $0.16 on Business
- ✓ Runs on whole lists, plus API and an MCP server for automation
- ✓ Pushes numbers to HubSpot, Salesforce, Pipedrive, Attio, or Close
Cons
- ✗ Mobile lookups need the person's LinkedIn URL
- ✗ No browser extension for one-click reveals while browsing
- ✗ DNC and TPS screening is not advertised, so run it in your dialer
- ✗ Credit math across many enrichment actions takes a few minutes to learn
Best for: Teams calling lists of hundreds or thousands of prospects across regions who want the highest find rate without stacking data subscriptions.
Pricing: Solo $49/mo (1,000 credits), Growth $99/mo (3,000), Pro $249/mo (10,000), Business $649/mo (40,000). A mobile costs 10 credits and a work phone 12. See SyncGTM pricing.
2. Lusha
Lusha pricing, October 2026 — a phone reveal costs 5 credits, an email 1
Lusha is a B2B contact database with a Chrome extension that reveals emails and phone numbers on LinkedIn profiles, Sales Navigator, and company websites. It claims 515M+ verified contacts, 132M of them in the United States, and states 85% US and 86% global phone accuracy.
The catch is the credit rule. A phone reveal costs 5 credits against 1 for a verified email, so the $49.90 Starter plan's 400 monthly credits cover 80 phone numbers, or $0.62 each.
Annual billing cuts that to about $0.47 per phone, but unused annual credits reset at the end of the cycle. Our Lusha review covers the extension and data quality in depth, and Lusha alternatives covers what to switch to.
Pros
- ✓ Fastest one-click reveal on LinkedIn, Sales Navigator, and company sites
- ✓ Free plan with 40 credits a month, about 8 phone numbers
- ✓ Claims 132M US contacts and 85% US phone accuracy
- ✓ ePrivacyseal GDPR certification, TrustArc CCPA validation, ISO 27701, SOC 2 Type II
- ✓ Monthly plans roll unused credits over, up to twice the limit
Cons
- ✗ A phone reveal costs 5 credits, so phone-heavy SDRs burn credits fast
- ✗ Works out to $0.44 to $0.62 per phone number
- ✗ Annual plans reset unused credits at the end of the cycle
- ✗ Single database: a miss stays a miss
Best for: US-focused SDRs who look up numbers one prospect at a time while browsing LinkedIn.
Pricing: Free (40 credits/mo); Starter $49.90/mo for 400 credits or $37.45/mo billed annually; Pro $69.90/mo for 600 credits or $52.45/mo annually; Premium $399.90/mo for 3,400 credits or $299.95/mo annually; Scale custom. Source: Lusha pricing.
3. Kaspr
Kaspr — LinkedIn phone lookups positioned on European contact data
Kaspris a LinkedIn Chrome extension that shows a prospect's phone number and email on their profile, group, or event page, with Sales Navigator support from Starter and Recruiter Lite on Business. It is owned by Cognism and leads with European data, claiming 500M+ phone numbers and emails across 200M+ profiles.
Phone credits sit in their own pool. Starter gives each user 100 a month, so a number costs $0.49 on annual billing or $0.65 month to month.
Business doubles that to 200 phone credits and adds 200 direct email credits. Our Kaspr review covers phone accuracy and the LinkedIn dependency in detail.
Pros
- ✓ Fast LinkedIn workflow across profiles, groups, events, and Sales Navigator
- ✓ Positioned on European contact data, with 150+ sources
- ✓ Unlimited B2B email credits on paid plans
- ✓ Sends numbers to Aircall and Ringover dialers
- ✓ Separate phone credit pool makes budgeting simple
Cons
- ✗ Starter includes only 100 phone credits a month
- ✗ Depends on LinkedIn as the starting point
- ✗ Priced per user, so costs grow with headcount
- ✗ API access is on request, and Enterprise needs 5+ users on annual billing
Best for: SDRs prospecting European accounts from LinkedIn at modest daily volume.
Pricing: Free (5 phone credits/mo); Starter $49/user/mo billed annually or $65 monthly, 100 phone credits/mo; Business $79/user/mo annually or $99 monthly, 200 phone credits/mo; Enterprise custom. Source: Kaspr pricing.
4. ContactOut
ContactOut — emails and phone numbers through an extension, search portal, and list enrichment
ContactOut finds personal emails, work emails, and phone numbers through a Chrome extension, a search portal, and list enrichment. It claims 800M people profiles and 100M direct dials.
The Email + Phone plan costs $99/mo, or $79/mo billed annually, with "unlimited" phones. Its terms cap that at 1,000 phone credits per account per month, which puts a number at roughly $0.08 to $0.10 if you use the full allowance.
Plans that exclude US and UK data cost about half: Email + Phone drops to $49/mo, or $39/mo annually. Our ContactOut review covers its email side and the one-user limit.
Pros
- ✓ Lowest cost per number at volume: about $0.08 to $0.10 at the fair-use cap
- ✓ Claims 100M direct dials across 800M profiles
- ✓ Built-in cloud phone dialer
- ✓ Plans without US and UK data cost about half
Cons
- ✗ Self-serve plans allow one user per company
- ✗ Unlimited phones are capped at 1,000 a month by the fair-use policy
- ✗ Exports are limited to 600 a month
- ✗ Team seats and API access are quote-based
Best for: A solo rep, founder, or recruiter who calls a lot and wants the lowest price per number.
Pricing: Free (5 phones a day, limited time); Email $49/mo or $39/mo annually; Email + Phone $99/mo or $79/mo annually; Team/API by quote. Sources: ContactOut pricing and fair use terms.
5. Seamless.AI
Seamless.AI — real-time contact search with a built-in engagement hub
Seamless.AI calls itself a real-time search engine rather than a static database: it searches for a contact when you ask, then verifies what it finds. It claims 1.8B+ verified business emails and 414M+ phone numbers.
Its public pricing pagedoes not list paid prices. Third-party guides put Basic at about $147/mo for 250 credits, and say one credit returns a contact's email and phone, which is about $0.59 per contact.
Seamless.AI refunds credits automatically for invalid emails. It does not advertise the same for wrong phone numbers, so check a sample of numbers before you load a dialer.
Pros
- ✓ Claims 414M+ phone numbers and 1.8B+ verified business emails
- ✓ Chrome extension works on any website, not only LinkedIn
- ✓ One credit reveals email and phone together, per third-party guides
- ✓ Built-in engagement hub for email, calls, and social steps
Cons
- ✗ Pricing beyond the free plan sits behind signup or a sales call
- ✗ Paid plans reportedly renew annually with a 60-day cancellation notice
- ✗ Users report uneven phone accuracy, so pilot first
- ✗ Automatic credit refunds cover invalid emails, not wrong numbers
Best for: US outbound teams that want lookup and calling in one tool and can run a pilot before signing.
Pricing: Free plan (reported at 50 credits; some 2026 guides report more); Basic about $147/mo for 250 credits per third-party reports; Pro and Enterprise by quote. Details in our Seamless.AI review.
6. Cognism
Cognism Diamond Data — mobiles verified by a person calling the number
Cognism is a B2B data platform built around Diamond Data: mobile numbers its team verifies by calling and confirming the right person picks up. It claims 10M+ phone-verified contacts and checks numbers against 16 Do Not Call lists.
In a study of 1,000 mobile contacts that Cognism publishes on its Diamond Data page, verified numbers reached the right person 45% of the time against 18% for standard numbers. Treat it as a vendor-published figure.
One credit reveals one contact, viewing that contact again is free, and credits are spent again only when key details change, such as a job move.
Pros
- ✓ Diamond Data mobiles are phone-verified by Cognism's team
- ✓ Screens numbers against 16 Do Not Call lists globally
- ✓ Strongest coverage in the UK and Western Europe
- ✓ Viewing a revealed contact again is free
Cons
- ✗ No published prices; every plan is quote-based
- ✗ Earlier contracts were reported at $15,000+ a year
- ✗ US mobile coverage is reported as good, not exceptional
- ✗ Intent data needs Pro, and CRM Enrichment is an add-on
Best for: Mid-market and enterprise teams calling UK and EU buyers who need DNC-screened mobiles and can sign an annual contract.
Pricing: Standard and Pro plans with 5 seats included, by quote. Earlier contracts were reported at about $15,000 a year plus per-user fees. See Cognism pricing and our Cognism review.
Phone Number Lookup Tools Compared
Here are the six phone number lookup tools side by side on region, verification, compliance, and entry price.
| Tool | Strongest region | Verification | Compliance | Entry price |
|---|---|---|---|---|
| SyncGTM | Mixed global lists | Waterfall across 50+ providers; 1-credit mobile verify step | DNC screening not advertised; run it in your dialer | $49/mo, 1,000 credits |
| Lusha | US (132M US contacts claimed) | Claims 85% US, 86% global phone accuracy | ePrivacyseal GDPR, TrustArc CCPA, ISO 27701, SOC 2 Type II | Free 40 credits; $49.90/mo |
| Kaspr | Europe | 150+ sources (vendor claim) | GDPR aligned, CCPA | Free 5 phones/mo; $49/user/mo annual |
| ContactOut | US/UK on global plans; cheaper plans exclude both | Claims triple verification | GDPR and CCPA compliant (vendor claim) | Free 5 phones/day; $79/mo annual |
| Seamless.AI | US | Real-time search; credit refund on invalid emails only | GDPR, CCPA, SOC 2 Type II, ISO 27001 | Free plan; Basic ~$147/mo (reported) |
| Cognism | UK and Western Europe | Diamond Data phone-verified mobiles (10M+) | Screens against 16 Do Not Call lists globally | Quote; reported $15,000+/yr |
Cost Per Verified Number
On self-serve plans in October 2026, a B2B phone number costs between about $0.08 and $0.65. The spread comes from credit rules, not headline prices.
| Tool | Entry plan | Numbers included | Cost per number | Credit rule |
|---|---|---|---|---|
| SyncGTM | Solo $49/mo (1,000 credits) | 100 mobiles | $0.49, falling to ~$0.16 on Business | Mobile 10 credits, work phone 12; misses not billed |
| Lusha | Starter $49.90/mo (400 credits) | 80 phones | $0.62 monthly, ~$0.47 annual | 5 credits per phone, 1 per email |
| Kaspr | Starter $49/user/mo annual ($65 monthly) | 100 phone credits | $0.49 to $0.65 | Separate phone credit pool |
| ContactOut | Email + Phone $79/mo annual ($99 monthly) | Up to 1,000 phones (fair use) | ~$0.08 to $0.10 at the cap | 600 exports/mo; one user per company |
| Seamless.AI | Basic ~$147/mo (third-party reports) | ~250 contacts | ~$0.59 per contact | 1 credit per contact, email and phone together (reported) |
| Cognism | Standard or Pro, quote only | Contract credit pool | Not published | 1 credit per revealed contact; re-views free |
Price per number is not price per conversation
What you pay for is a number that reaches the right person. Divide cost per number by your right-person connect rate to get cost per reachable contact.
Take two illustrative lists. A $0.10 number that reaches the right person 20% of the time costs $0.50 per real contact and takes 5 dials; a $0.50 number that connects 60% of the time costs about $0.83 and takes under 2 dials.
The cheaper list saves $0.33 per contact but costs a rep 3 extra dials. Once you count rep time, the higher-connect list almost always wins. These connect rates are hypothetical; measure yours in a pilot.
Two more costs hide in the fine print. Tools that bill for switchboard numbers or empty results raise your real price, and annual plans that reset unused credits raise it again if your team under-dials.
Coverage by Region
No phone lookup tool is strongest everywhere. Vendors build data where their customers call, so match the tool to your territory.
| Region | Strongest picks | Watch out for |
|---|---|---|
| United States and Canada | Lusha, Seamless.AI, ContactOut (global plan) | Personal mobiles fall under the TCPA; dial manually or with consent. |
| UK and Ireland | Cognism, Kaspr | Screen against TPS and CTPS before live marketing calls. |
| France, DACH, Benelux, Nordics | Kaspr, Cognism | Germany needs at least presumed consent for B2B cold calls. |
| APAC, LatAm, Middle East | No single source leads; use a multi-provider waterfall and pilot first | Hit rates vary most here, so test 50 contacts before buying. |
For deeper regional rankings, see the best phone databases for North America and the best phone databases for Europe. Country guides such as the UK phone number database cover single markets.
Calling Compliance: DNC, TCPA, TPS, and GDPR
Finding a number is legal in most markets; how you call it is where the rules apply. Here is the short version for the regions most B2B teams dial. It is not legal advice.
United States
The FTC's National Do Not Call Registry guidance says the rules largely do not cover business-to-business calls. The FCC's TCPA rules are separate, and they restrict autodialed or prerecorded calls and texts to mobile numbers without prior consent.
In practice, scrub personal mobiles against the registry, and dial them manually unless you have consent.
United Kingdom
Under PECR, you must not make live marketing calls to numbers registered with the Telephone Preference Service (TPS) or Corporate TPS unless the person has consented. The ICO's telephone marketing guidance covers the details, and sole traders count as individuals.
European Union
Under GDPR, most B2B calling relies on legitimate interest under Article 6(1)(f). Because the data came from a vendor, Article 14 also requires you to tell the person where you got it.
Country rules stack on top: Germany, for example, needs at least presumed consent before a B2B cold call.
What to ask a vendor
- Does it flag or screen numbers against DNC, TPS, and CTPS lists, and how often?
- Does it label mobiles separately from direct dials and switchboards?
- Can it show where a record came from, for GDPR Article 14 notices?
- How does it handle opt-out and erasure requests?
How to Test a Lookup Tool Before You Buy
The only accuracy number that matters is the one you measure on your own ICP. A 50-contact pilot takes an afternoon and beats any vendor claim.
- Pick 50 real prospects from your target accounts, split across the regions you call.
- Run them through each tool's free plan or trial, using the same lookup method your reps will use.
- Record the find rate, then the share of results that are mobiles or direct dials rather than switchboards.
- Dial every number and count right-person connects, wrong people, and dead lines.
- Divide plan cost by right-person connects to get your real cost per conversation.
Lusha's 40 free monthly credits, Kaspr's 5 free phone credits, and ContactOut's 5 free phones a day are enough for a small first pass.
How to Choose
Match the phone number lookup tool to how your team calls:
- "We call UK and EU buyers and need DNC-screened mobiles." Cognism.
- "Reps reveal numbers one at a time on LinkedIn, mostly US." Lusha.
- "We prospect European accounts on LinkedIn on a budget." Kaspr.
- "One person, lots of numbers, lowest price per number." ContactOut.
- "We want search, dialing, and sequences in one US tool." Seamless.AI, after a pilot.
- "We call whole lists across regions and want the most numbers found." SyncGTM, because its waterfall tries the next provider when the first one misses.
Final Verdict
Cognism is the best phone number lookup tool for teams calling the UK and Europe, thanks to phone-verified mobiles and DNC screening across 16 lists. Its quote-only pricing, reported from $15,000 a year, puts it out of reach for small teams.
Lusha is the quickest LinkedIn reveal for US prospects, Kaspr the cheapest European LinkedIn option, and ContactOut the lowest price per number for a single heavy user. Seamless.AI suits US teams that want lookup and calling in one tool, after a pilot.
SyncGTM ranks first for list-based calling, because one subscription queries 50+ providers and bills only the numbers it finds. If single-source tools leave too many gaps in your call lists, SyncGTM plans start at $49/mo, and you can run a Find Mobile Number column on your next list today.