# Best B2B Phone Data APIs in 2026

Lusha, Cognism, Prospeo, People Data Labs and RocketReach compared as phone data APIs on lookup inputs, phone fields, charges on misses, rate limits and Do Not Call handling.

Adding phone numbers to contacts from code is a different purchase from buying seats in a contact database. What matters is what the API accepts, what it returns, what a miss costs and how hard you can call it.

- Lusha is the best B2B phone data API for self-serve teams, with an API key on every plan.
- Cognism suits UK and Europe calling teams, with phone-verified mobile data scrubbed against 16 DNC lists.
- Prospeo charges nothing when no result is found and can return only records with a mobile.
- People Data Labs fits product teams enriching at volume, billed per match with high rate limits.
- RocketReach fits async workflows, with free re-lookups and no credit charged when no data is found.

These picks apply to teams calling business contacts in the US, the UK and Europe who enrich numbers from code, a CRM workflow or a dialer integration. The ranking rests on each API's documented inputs, billing, rate limits and access route. Run a matched test on your own records before committing volume.

## Best B2B Phone Data APIs Compared

Lusha, Cognism, Prospeo, People Data Labs and RocketReach all return business phone numbers through an API, but they differ on what you must send, what a lookup costs when no number comes back, and how fast you can call them. Those three differences decide how much engineering a phone enrichment job needs and what each dialable number really costs.

The table below compares the five [phone and direct-dial data](https://growthtribune.com/prospecting-data/direct-dial-data/) APIs on the mechanics a builder meets first. The first two columns show each vendor's free plan and API status, and the typed columns summarise its documented API terms.

| Tool | Free plan | Public API | Lookup inputs | Charged on no match | Best for |
| --- | --- | --- | --- | --- | --- |
| Lusha | Yes | Yes | Email, LinkedIn, name plus company | Yes, 1-credit minimum | Self-serve US and UK teams |
| Cognism |  | Yes | Email, LinkedIn, company domain | Only on redeem | UK and Europe calling teams |
| Prospeo | Yes | Yes | Name plus company, LinkedIn, email | No | Mobile-only outbound lists |
| People Data Labs | Yes | Yes | Email, phone, LinkedIn, name | No, per match only | High-volume product teams |
| RocketReach | Yes | Yes | Name plus employer, LinkedIn, email | No | Async, webhook-ready teams |

The charge on no match is where the five differ most. Lusha is the one API of the five that bills a lookup that returns nothing, with a minimum of 1 credit per request. Cognism spends credits only when a contact is redeemed, and Prospeo, People Data Labs and RocketReach charge only when data comes back.

Inputs matter as much. A team that holds only LinkedIn URLs can use any of the five, while a team that holds names and company domains needs an API that matches on them.

## How We Chose These Phone Data APIs

To make this list, a tool needed a documented API that returns phone numbers for a named business contact and documentation that says what a lookup costs, and five tools met that bar.

Each tool had to clear three bars:

- A documented, callable API that returns phone numbers for a named business contact
- Documentation that states the accepted inputs and how lookups are billed
- Self-serve access or a stated route to API access

Tools that cleared the bar were then compared on six criteria, in this order:

- Lookup inputs the API accepts
- Phone fields returned, and whether results can be filtered to mobiles
- Billing when a lookup finds nothing
- Documented rate limits and error handling
- Do Not Call handling
- The team each one fits

The ranking rests on each API's documented inputs, billing, rate limits and access route. Hit rates vary with the list you send, so measure them in your own matched test, set out in the section on choosing an API.

Platforms built mainly as contact databases, rated on coverage, refresh cycles and email verification, are covered in our guide to the [best B2B contact databases](https://growthtribune.com/best-b2b-contact-databases/). This post stays on phone numbers delivered through an API.

Three tools that recur on ranking lists were considered and left out:

**Considered, not included**

| Tool | Why it was left out |
| --- | --- |
| Apollo | Phone reveals sit inside a prospecting and sequencing platform, not a standalone phone data API |
| Clay | Orchestrates other providers' data in workflows rather than holding its own phone data |
| Coresignal | Company, employee and job data from the public web, not contact phone numbers |

## Lusha

Lusha gives every user an API key on every plan, including Free, and charges 5 credits to reveal a phone number against 1 credit for an email, with a minimum of 1 credit per request even when no data comes back. Any Lusha user can start calling the API on a key, and every miss still carries a cost.

**Lusha**

Lusha is a B2B contact and company data platform for sales, marketing and recruiting teams. Its Person API and Bulk Person API serve sales and RevOps teams that want phone numbers in a CRM or dialer without a sales call to unlock access.

**Verdict:** A self-serve key on every plan and documented rate limits, held back by its charge on empty lookups.

**Lookup inputs:** The Person API accepts an email, a LinkedIn URL, or a first and last name with a company name or domain. The Bulk Person API takes up to 100 contacts per request.

**Billing on misses:** A phone reveal costs 5 credits and an email reveal 1 credit. A minimum of 1 credit applies to every request, even when nothing is returned.

**Rate limits and errors:** Limits are set per minute, per hour and per day by plan. Free and Starter allow 40 requests a minute and 100 a day, Pro 50 a minute and 1,500 a day, Premium 300 a minute and 18,000 a day, and Scale 300 a minute and 50,000 a day. Responses carry x-minute-requests-left, x-hourly-requests-left and x-daily-requests-left headers. A 429 means the rate limit or daily quota is spent, and Lusha's advice is to wait for the window to reset.

**DNC handling:** The Lusha platform supports Do Not Call tables for the UK (TPS and CTPS) and the US. Numbers on the tables a user selects are hidden across Lusha while other data points stay visible, and Lusha tells users to make sure their outreach complies before calling. Treat this as a platform setting and keep your own screening step for numbers that go from the API to a dialer.

**Pricing:** Lusha bills the API in credits. Each phone reveal uses 5 credits against 1 for an email, and every request uses at least 1 credit, even when it returns nothing.

**Best fit:** Self-serve teams starting small that call US or UK contacts and want a working key the same day.

**Limitation:** Empty lookups still cost at least 1 credit each, which adds up on a list with a low match rate. Check the mix of mobile, direct-dial and office lines in a matched test before routing Lusha numbers to a dialer.

## Cognism

Cognism's API spends credits only when a contact is redeemed, and returns mobile and direct-dial numbers only when the account's API entitlements include them, which Cognism's provisioning team sets after account-manager approval. Search and enrich calls cost nothing, so spend follows the contacts you keep.

**Cognism**

Cognism is a B2B sales intelligence platform with contact and company data, strongest in European markets. Its API serves teams that call into the UK and Europe and want that data in their own systems.

**Verdict:** The pick for calling into the UK and Europe, with phone-verified mobiles in its data and scrubbing against 16 DNC lists, held back by API phone access that runs through an account manager.

**Lookup inputs:** The API has Search, Enrich and Redeem endpoints. Enrich takes an email, a LinkedIn profile, a company domain or a website.

**Phone fields returned:** Mobile and direct-dial numbers come back only when the account's API entitlements include them. The subscription includes API access, and the Provisioning team sets entitlements after Account Manager approval. Behind the API, Cognism's Diamond Data programme calls numbers to confirm the right person picks up, offers verification on request in less than 48 hours, and counts more than 10 million phone-verified contacts globally.

**Billing on misses:** Search and Enrich use no credits. Credits are consumed only when a contact record is redeemed, and redeeming the same contact again costs nothing extra.

**DNC handling:** Cognism scrubs its data against 16 DNC lists globally, including registries in the US, the UK (TPS and CTPS), France, Germany and Australia.

**Pricing:** Cognism's plans are shown below. Spend depends on how many contacts you redeem, since search and enrich calls use no credits.

**Cognism pricing**

| Plan | Price | Billing | Notes |
| --- | --- | --- | --- |
| Pro (Sales prospecting) | Custom pricing | per custom | per seat |
| Standard (Sales prospecting) | Custom pricing | per custom | per seat |

**Best fit:** Calling teams working the UK and Europe that need mobiles confirmed by phone and DNC scrubbing across several countries.

**Limitation:** Phone fields in the API depend on contracted entitlements, so getting mobiles through the API is a sales conversation rather than a self-serve key.

> **Note:** In a study Cognism publishes, an organisation it describes as independent called 1,000 mobiles and reached the right person on 45% of Cognism-verified numbers against 18% of standard mobiles, which Cognism headlines as a 3x connect rate. The study is Cognism's own claim, so treat it as a vendor figure and test on your own list.

## Prospeo

Prospeo's Enrich Person API charges 10 credits for each mobile it finds, includes the email at no extra cost, and charges nothing when no result is found. For an outbound team that only wants contacts it can call, that billing rule matters more than database size.

**Prospeo**

Prospeo finds verified business emails and mobile numbers for sales teams. Its Enrich Person API suits outbound teams that pay per result and want only records with a mobile.

**Verdict:** The best fit for paying only for mobiles found, with a filter that drops records without one.

**Lookup inputs:** Enrich Person accepts a first and last name or a full name with a company identifier, a LinkedIn URL, a work email or a person\_id. Prospeo advises against matching on company\_name alone.

**Phone fields returned:** Set enrich\_mobile to add a mobile when one exists, or only\_verified\_mobile to return only records that have one. The person.mobile object returns status, revealed, mobile, mobile\_national, mobile\_international, mobile\_country and mobile\_country\_code, and the number is masked when revealed is false.

**Billing on misses:** An email costs 1 credit and a mobile 10 credits, with the email included free when a mobile is requested. No credit is charged when no result is found, and re-enriching the same record within 90 days is free.

**Rate limits and errors:** Requests over the limit return HTTP 429 with the message "Rate limit exceeded".

**Pricing:** Prospeo's plans are shown below. Spend tracks the mobiles found, since lookups that return nothing cost no credits.

**Prospeo pricing**

| Plan | Price | Billing | Notes |
| --- | --- | --- | --- |
| Free | $0 | per month |  |
| Starter | $49 | per month | per user |
| Growth | $99 | per month | per user |
| Pro | $249 | per month | per user |

**Best fit:** Outbound teams that want a list of dialable mobiles and nothing else, and that send names with a company or a LinkedIn URL.

**Limitation:** Salesforge, a competing vendor that reviews Prospeo, notes that [the Free plan has no API access](https://www.salesforge.ai/blog/prospeo-review) and that mobiles at 10 credits add up when a whole list is enriched without filtering.

## People Data Labs

People Data Labs bills its Person Enrichment API per match, returns a 404 when no match is found, and lets you require that phone\_numbers be present before a response counts as a match. That suits product and data teams that enrich at volume from code and want to pay only for usable records.

**People Data Labs**

People Data Labs is a B2B person and company data provider that sells profile datasets and enrichment APIs to developers and data teams. Its Person Enrichment API suits teams building phone enrichment into a product or a data pipeline.

**Verdict:** The fit for high-volume enrichment from code, with per-match billing and 1,000 requests a minute on paid accounts, for teams that build their own retries and screening.

**Lookup inputs:** Any one of profile, email, phone, email\_hash or lid (a LinkedIn ID) is enough to match. Otherwise send a name plus one of locality, region, company, school, location or postal\_code. Phone inputs must begin with a plus sign and the country code.

**Phone fields returned:** The min\_likelihood parameter sets the confidence a match needs before a 200 comes back, and required names fields that must be present, such as phone\_numbers. People Data Labs' own dataset statistics count 470,206,255 records with a mobile\_phone value in data version 36.0, a vendor count of records rather than an accuracy figure.

**Billing on misses:** People Data Labs charges per match. A 200 is a match and a 404 is no match.

**Rate limits and errors:** The default limit is 100 requests a minute for free customers and 1,000 a minute for paying customers.

**Pricing:** People Data Labs' plans are shown below. Phone numbers, emails and addresses are obfuscated on the free tier, so contact data needs Pro. Premium fields are add-ons priced separately.

**People Data Labs pricing**

| Plan | Price | Billing | Notes |
| --- | --- | --- | --- |
| Free (Testing) | $0 | per month | per credit |
| Pro (Self-Serve), annual billing | $940 | per year | per credit |
| Pro (Self-Serve), monthly | $98 | per month | per credit |
| Enterprise (Bulk Data) | Custom pricing | per custom | per credit |

**Best fit:** Product and data teams enriching large record sets from code, with their own engineering for retries and suppression.

**Limitation:** People Data Labs is built for developers and data teams, so plan Do Not Call screening in your own pipeline before its numbers reach a dialer, and phone data starts on a paid plan.

## RocketReach

RocketReach charges no credit when a lookup finds no data and makes re-lookups free while a plan is active, but its Person Lookup runs asynchronously, so results arrive through a status check or a webhook. Teams with webhook handling already in place get the most from it.

**RocketReach**

RocketReach is a lead intelligence database for finding professionals' email addresses, phone numbers and social profiles. Its People Data API suits teams that can process lookups asynchronously and re-check contacts often.

**Verdict:** A good fit for asynchronous workflows and frequent re-checks, ranked fifth because a number needs a status check or a webhook before it is usable.

**Lookup inputs:** Person Lookup accepts a name with current\_employer, a linkedin\_url, an email, a phone in E.164 or international format, or a RocketReach ID. Lookups move from progress to complete, and full verified results come from /checkStatus or a webhook.

**Billing on misses:** A premium credit is charged for an A or A- grade email or a valid phone, and a standard credit for email only. No credit is charged when no data is found, and re-lookups and updates are free while the plan is active. Paid API plans also include about 10,000 free searches a day.

**Rate limits and errors:** Person Lookup limits run from 15 requests a minute on Essentials, 50 on Pro and 100 on Ultimate to 250 on Custom, with hourly, daily and monthly caps per plan. A global limit of 10 requests a second applies across all APIs on every plan.

**Pricing:** RocketReach's plans are shown below. Each export uses 1 API credit, so spend tracks the numbers you pull rather than the searches you run.

**RocketReach pricing**

| Plan | Price | Billing | Notes |
| --- | --- | --- | --- |
| Essentials (Email Only) | $33 | per month, billed annually | per seat |
| Pro (Email + Phone) | $75 | per month, billed annually | per seat |
| Ultimate (Email + Phone) | $142 | per month, billed annually | per seat |
| Custom Team (plans start at $6K annually) | Custom pricing | per custom |  |

**Best fit:** Teams with webhook infrastructure that re-check contacts often and can wait for a lookup to complete.

**Limitation:** Asynchronous lookups mean polling or webhook handling before a number is usable in a dialer, which adds build work for teams that expect a number in the first response.

## How To Choose A B2B Phone Data API

Choose a B2B phone data API by the inputs you already hold, whether it labels or filters mobile numbers, and whether a lookup that returns nothing still costs a credit, before comparing database size. Then check the access route, the rate limits and where Do Not Call screening happens.

Work through the criteria in this order:

1. **Match the inputs you hold.** All five APIs accept a LinkedIn URL or profile. Lusha, Prospeo and People Data Labs also match on a name with a company, RocketReach on a name with current\_employer, and Cognism's Enrich on an email, a company domain or a website. Prospeo advises against matching on company name alone.
2. **Check the phone fields and line type.** Prospeo returns a mobile object, and only\_verified\_mobile filters to records that have one. People Data Labs' required parameter can demand phone\_numbers before a match counts. Cognism returns mobile and direct-dial numbers by entitlement. For Lusha and RocketReach, measure the mix of mobile, direct and office lines in your test before routing numbers to a dialer.
3. **Find out what a miss costs.** Lusha charges at least 1 credit per request. Prospeo, RocketReach and People Data Labs charge only on a match, and Cognism only on redeem.
4. **Confirm the access route.** Lusha issues a key on every plan. Cognism's phone fields need entitlements approved through an account manager. People Data Labs obfuscates phone numbers on its free tier, and Prospeo's Free plan has no API access.
5. **Plan for rate limits and async calls.** Documented limits range from 15 requests a minute on RocketReach's Essentials plan to 1,000 a minute on a paid People Data Labs account. RocketReach also returns results asynchronously.
6. **Decide where DNC screening happens.** Across its platform, Lusha hides numbers on the UK and US tables a user selects, and Cognism scrubs its data against 16 lists. Whichever API you pick, screening numbers before they reach a dialer is your duty, so build that step into your own pipeline.

**What to ask before you buy**

| Criterion | What to ask the vendor |
| --- | --- |
| Inputs | Which fields does a match need, and does company name alone work? |
| Phone fields | Is each number labelled mobile, direct dial or office? |
| Mobile filter | Can I return only records that have a mobile? |
| Misses | Is a lookup that returns nothing charged? |
| Access | Is the API on my plan, or set by entitlement? |
| Limits | What are the per-minute and daily caps, and what does a 429 return? |
| DNC | Are numbers screened, and against which registries? |

Treat published connect-rate claims, including Cognism's own study, as vendor figures until your own test agrees with them.

The test that settles the choice is a matched one. Take one sample of known contacts from your CRM, send the same records to each API, and log for each tool the match, the line type, the credits spent and the response time. Then have reps call the returned numbers and score right-person pickups, the one outcome that pays for the data. The same method you would use to [evaluate B2B database coverage before buying](https://growthtribune.com/how-to-evaluate-b2b-database-coverage-before-buying/) applies, scoped to phone numbers.

Keep the sample matched to the contacts you plan to call. A test on a different region or seniority than your real list tells you little about the numbers you will pay for.

## What Does A B2B Phone Data API Cost?

The real cost of a B2B phone data API is credits per dialable number, which depends on whether a phone costs more than an email and whether lookups that return nothing are charged, as they are at Lusha with a one-credit minimum per request. Plan prices sit in each tool's pricing table above.

**What drives the bill**

| Tool | What a number costs | Charge when nothing returns |
| --- | --- | --- |
| Lusha | 5 credits a phone, 1 an email | At least 1 credit per request |
| Cognism | Credits on redeem only | None for search or enrich |
| Prospeo | 10 credits a mobile, email included | None |
| People Data Labs | Billed per match | None, a 404 is not billed |
| RocketReach | Premium credit for a valid phone | None |

A phone reveal costs several times an email reveal, so the headline credit count on a plan overstates how many numbers it buys. At Lusha a phone uses 5 credits against 1 for an email. At Prospeo a mobile uses 10 credits, with the email included.

**Worked example:** Take 1,000 contacts sent one per request, where 400 return a phone number and only the phone is revealed. At Lusha, the 400 reveals cost 2,000 credits and the 600 empty requests cost at least 600 more, about 2,600 credits, or 6.5 credits per dialable number. At Prospeo, the 400 mobiles cost 4,000 credits and the 600 misses cost nothing, 10 credits per dialable number with the email included.

The two totals are not directly comparable, because a credit is priced differently on each vendor's plans. Convert each total with the plan prices in the pricing tables, and rerun the sum at your own match rate. The lower the match rate, the more Lusha's minimum charge weighs.

Four other drivers change the bill:

- **Free re-lookups.** RocketReach makes re-lookups free while a plan is active, Prospeo re-enriches the same record free within 90 days, and Cognism charges nothing to redeem the same contact again.
- **Expiring credits.** A review by Salesforge, a competing vendor, reports that Prospeo's unused credits expire at renewal, so buy volume you will use within the term.
- **Plan gates.** People Data Labs obfuscates phone numbers on its free tier, and Prospeo has no API on its Free plan, so phone enrichment starts on a paid plan at both.
- **Add-ons.** People Data Labs prices premium fields as add-ons, separate from its plans.

## How To Handle Phone Data API Rate Limits

People Data Labs allows 1,000 enrichment requests a minute on paid accounts, while RocketReach caps every plan at 10 requests a second across its APIs, so the same enrichment job can need very different batching and retry logic. Size each job against the documented limit before you schedule it.

**Documented limits and what to build**

| Tool | Documented limits | What to build |
| --- | --- | --- |
| Lusha | 40 to 300 a minute, 100 to 50,000 a day | Read remaining-request headers, wait on 429 |
| People Data Labs | 100 a minute free, 1,000 paid | Throttle to the per-minute cap |
| Prospeo | Returns 429 when over the limit | Back off and retry on 429 |
| RocketReach | 15 to 250 a minute, 10 a second overall | Webhooks rather than tight polling |

Five rules keep an enrichment job inside its limits:

- **Read the remaining-requests headers.** Lusha returns x-minute-requests-left, x-hourly-requests-left and x-daily-requests-left on each response, so slow down before the count reaches zero.
- **Back off and retry on 429.** Lusha and Prospeo both return 429 when a limit is hit. Wait, then retry with a growing delay until the window resets.
- **Batch through bulk endpoints.** Lusha's Bulk Person API takes up to 100 contacts per request, which uses far fewer requests than single lookups.
- **Cache results.** Store every number you receive, so repeat checks fall inside Prospeo's 90-day and RocketReach's active-plan free re-lookup windows.
- **Use webhooks for async lookups.** RocketReach lookups move from progress to complete, so a webhook beats polling /checkStatus in a tight loop against a 10-requests-a-second ceiling.

A generic retry pattern with exponential backoff looks like this:

**Retry with exponential backoff**

```js
const sleep = (ms) => new Promise((resolve) => setTimeout(resolve, ms));

async function callWithBackoff(sendRequest, maxAttempts = 6) {
  let delay = 1000;
  for (let attempt = 1; attempt <= maxAttempts; attempt++) {
    const response = await sendRequest();
    if (response.status !== 429) return response;
    await sleep(delay + Math.random() * 500);
    delay = Math.min(delay * 2, 60000);
  }
  throw new Error("Rate limit still exceeded after retries");
}
```

The random jitter stops parallel workers from retrying in lockstep. Cap the number of attempts, log every 429, and pause the job when a daily quota is spent rather than retrying until the next day.

## Is It Legal To Call Mobile Numbers From A B2B Data API?

Under the FCC's rules, [autodialed or prerecorded calls to a wireless number need the recipient's consent](https://www.fcc.gov/cgb/consumerfacts/robocalls.pdf), so a mobile number returned by a B2B data API should go to a manual dialer unless consent is on record. In the UK, live business calls need TPS and CTPS screening first.

In the US, the FTC says [most sales calls to a business are exempt from the Do Not Call provisions](https://ftc.gov/business-guidance/resources/qa-telemarketers-sellers-about-dnc-provisions-tsr-0) of the Telemarketing Sales Rule. That exemption concerns the registry, not the dialer. The FCC's consumer guide makes no carve-out for business-owned wireless numbers, so a mobile from an API changes which dialer you can use.

In the UK, the ICO says that before live B2B calls you must [screen against both the CTPS and TPS registers](https://ico.org.uk/for-organisations/direct-marketing-and-privacy-and-electronic-communications/business-to-business-marketing/). Sole traders and some partnerships count as individual subscribers, and the UK GDPR applies to personal data used for direct marketing even in a business context.

Some tools help with screening. Lusha hides numbers on the UK TPS, UK CTPS and US tables you select, and Cognism scrubs its data against 16 DNC lists. Lusha itself tells users to make sure their outreach complies before calling.

> **Warning:** DNC hiding in a data tool does not move the legal duty. The caller still has to screen numbers, hold consent for autodialed or prerecorded calls to mobiles, and meet UK GDPR duties for business contacts' personal data.

This section is general information, not legal advice.

## Which B2B Phone Data API Should You Choose?

If you need mobile numbers only and want to pay only for numbers found, Prospeo's only\_verified\_mobile filter and free misses fit best; if you call into Europe, Cognism's phone-verified mobiles and 16 DNC lists fit best. The other three picks depend on how you build and who you call.

Use one decision rule per team:

- **Self-serve team starting small, calling US or UK contacts:** Choose Lusha, for a key on every plan and documented rate limits.
- **Team calling across the UK and Europe:** Choose Cognism, for phone-verified mobiles and scrubbing against 16 DNC lists.
- **Outbound team paying per result that wants only contacts with a mobile:** Choose Prospeo, for only\_verified\_mobile and no charge on misses.
- **Product or data team enriching at volume from code:** Choose People Data Labs, for per-match billing and 1,000 requests a minute on paid accounts.
- **Team with webhook infrastructure that re-checks contacts often:** Choose RocketReach, for free re-lookups while a plan is active and asynchronous lookups.

- Best for: Self-serve teams calling US or UK contacts
- Not for: Lists with low match rates, where every empty request costs a credit

- Best for: Calling teams working the UK and Europe
- Not for: Teams that want a self-serve key without an account manager

- Best for: Outbound teams that want only contacts with a mobile
- Not for: Teams enriching whole lists without filtering, at 10 credits a mobile

- Best for: Product and data teams enriching at volume from code
- Not for: Sales teams that want dialer-ready numbers without building a pipeline

- Best for: Teams with webhooks that re-check contacts often
- Not for: Workflows that need a number in the first response

Before you test any of them, [turn an ICP into prospecting filters](https://growthtribune.com/how-to-turn-an-icp-into-prospecting-filters/) so the test sample matches the contacts your reps will actually call.

## Frequently Asked Questions

**Is there a free B2B phone data API?**

Lusha issues an API key on every plan, including Free, though each phone reveal uses 5 credits against 1 for an email. People Data Labs obfuscates phone numbers on its free tier, and a review by Salesforge, a competing vendor, reports that Prospeo's Free plan has no API access.

**What is the difference between a direct dial and a mobile number?**

A direct dial is a business line that rings one person's desk without going through a switchboard, while a mobile number reaches the person's own phone wherever they are. Cognism returns both through its API when the account's entitlements include them. In the US, autodialed calls to mobiles need the recipient's consent.

**Do phone data APIs charge when no number is found?**

Most B2B phone data APIs charge only when a lookup returns data, as Prospeo, RocketReach and People Data Labs do, but Lusha charges at least one credit per request even when nothing comes back. Cognism spends credits only when a contact is redeemed, and its search and enrich calls use none.

**Can a phone data API check numbers against Do Not Call lists?**

Some vendors screen their data. Across its platform, Lusha hides numbers on the UK TPS and CTPS tables and the US tables a user selects, and Cognism scrubs its data against 16 DNC lists globally. In every case the legal duty to screen numbers and meet calling rules stays with the caller, not the data vendor.

## Sources

- [Prospeo Review](https://www.salesforge.ai/blog/prospeo-review), salesforge.ai
- [Stop Unwanted Robocalls and Texts (FCC consumer guide)](https://www.fcc.gov/cgb/consumerfacts/robocalls.pdf), fcc.gov
- [Q&A for Telemarketers & Sellers About DNC Provisions in TSR](https://ftc.gov/business-guidance/resources/qa-telemarketers-sellers-about-dnc-provisions-tsr-0), ftc.gov
- [Business-to-business marketing (ICO)](https://ico.org.uk/for-organisations/direct-marketing-and-privacy-and-electronic-communications/business-to-business-marketing/), ico.org.uk

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Source: https://growthtribune.com/best-b2b-phone-data-apis/