How to Find Someone's Cell Phone Number for B2B Outreach (API)

You find a B2B cell number in two calls: search with hasPhone set to true, then look up each person by id. The search tells you who holds a number before you spend anything on a lookup. This guide runs both against the LeadOcean API with real queries.

TL;DR

• Size the list for free with a count, search only people who have a number, then call GET /v2/people/phone on each.
• It takes about 15 minutes. A 10-person test spends 20 records: 10 for the search rows, 10 for the lookups.
• The Free plan covers it: 1,000 records for life, no card, 5 requests a second.

Prerequisites

• A LeadOcean API key from app.leadocean.io, exported as $LEADOCEAN_API_KEY. The key needs the search and enrich scopes. Free keys get both.
• curl and jq.
• A target in mind: a job level, a function and a country. This guide uses VPs of Sales in the US.

Step 1: Size the list for free

Count first. A count spends no records, so you can tune filters until the list is the right size.

Send count=true as a query parameter, with limit=1. The JSON body rejects unknown fields, so keep the flag in the URL.

curl -s -X POST "https://api.leadocean.io/v1/people/search?count=true&limit=1" \
  -H "x-api-key: $LEADOCEAN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "jobLevel": ["VP"],
    "jobFunction": ["Sales & Business Development"],
    "country": ["US"],
    "hasPhone": true
  }' | jq '.meta | {total, countOnly}'

meta.total is capped at 100,000 on this route. If you use Claude or another MCP client, the leadocean_count_leads tool gives the exact figure with breakdowns. We ran it on 2026-10-21 with the same four filters and got 275,259 people.

Filter values are exact strings. VP and Sales & Business Development must match the enum. Check them with GET /v1/enums or the leadocean_list_enum_values tool before you guess.

Step 2: Search only people who hold a number

Run the same filters without the count flag. hasPhone: true keeps rows where a number exists, so every lookup in step 3 has something to find.

curl -s -X POST "https://api.leadocean.io/v1/people/search" \
  -H "x-api-key: $LEADOCEAN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "jobLevel": ["VP"],
    "jobFunction": ["Sales & Business Development"],
    "country": ["US"],
    "hasPhone": true,
    "limit": 10
  }' > people.json

jq -r '.data[].meta.source_ids.person_id' people.json > ids.txt
wc -l ids.txt

The body is flat JSON and every filter is an array of strings, except hasPhone, which is a boolean. limit runs from 1 to 100. Page with meta.nextCursor passed back as cursor.

Search rows carry no phone numbers. They carry has_phone, and an id at meta.source_ids.person_id. That id is what you send in the next step. Each row returned costs 1 record, so 10 rows cost 10.

Step 3: Look up each number

Call the phone endpoint with the id. It returns every number held for that person, best first.

while read -r id; do
  curl -s -G "https://api.leadocean.io/v2/people/phone" \
    --data-urlencode "person_id=$id" \
    -H "x-api-key: $LEADOCEAN_API_KEY"
  echo
  sleep 0.25
done < ids.txt > phones.jsonl

Send exactly one identifier: linkedin_url, contact_id or person_id. person_id and contact_id are the same field, so send one of them. The sleep keeps you under the 5 requests a second on Free. Each call costs 1 record, including a call that finds nothing.

If you already hold a LinkedIn URL, skip steps 1 and 2 and send linkedin_url instead. The same pattern works in the other direction: find a LinkedIn profile from a phone number.

Step 4: Keep the mobile numbers

The array is ordered best first, and each number has a type. The type is the source's own label, so it is not a closed list. Treat any value you do not recognise as unknown.

jq -c 'select(.data.found == true)
  | {person_id: .data.person_id, mobile: ([.data.phones[] | select(.type == "mobile")][0].phone)}
  | select(.mobile != null)' phones.jsonl > mobiles.jsonl

wc -l mobiles.jsonl

This keeps one mobile number per person and drops people with only an office or direct line. Change the select to keep direct too if your reps call desks.

One warning on compliance. The v2 endpoint does not publish a do-not-call flag. The older GET /v1/people/phone returns dnc on each number, but it is not populated yet, and null means unknown, not safe to call. Run your own DNC and consent checks before anyone dials.

What you get

The response shape from the API reference, with placeholder values:

{
  "success": true,
  "data": {
    "person_id": "1234567",
    "found": true,
    "phones": [
      { "phone": "+14155550133", "type": "mobile" },
      { "phone": "+14155550134", "type": "office" }
    ],
    "best": { "phone": "+14155550133", "type": "mobile" }
  }
}

There is no meta object on this endpoint. The price per call is not reported in the body, so read GET /v1/usage for it. A person we hold nothing for returns found: false, and a record we cannot match at all is a 404.

The free count from step 1, run on 2026-10-21:

{
  "total": 275259,
  "totalIsExact": true,
  "distinctCompanies": 135386,
  "filters": "jobLevel VP, jobFunction Sales & Business Development, country US, hasPhone true"
}

That is a count of US VPs of Sales with a number on file. It says nothing about how many numbers are mobile or dialable.

Troubleshooting

FAQ