Reverse Email Lookup API: Identify a Lead from Their Work Email

A reverse email lookup API takes a work email address and returns what the provider knows about the person: typically name, job title, employer and a professional profile link. Business teams use it on inbound leads, where an address arrives with no context and someone must decide who it is worth answering first.

The problem on the inbound side

A demo request arrives from [email protected]. Is that a founder, an analyst or a student? Without context, every lead looks the same, so teams either answer all at the same speed or guess. Reverse lookup removes some of the guessing.

Two flavours exist. A company-level reverse lookup turns the email’s domain into a firm: size, industry, location. A person-level one goes further to the individual. Which you need depends on the question. If “what kind of company is this?” is enough, the company route is cheaper and carries fewer privacy concerns. BusinessMCP’s company data API takes a domain, URL or work email and returns the company, with name, industry, size, location, phone and LinkedIn, at $0.02 per call when found.

The person-level endpoint

For the individual, BusinessMCP’s enrichment endpoint accepts email (up to 320 characters) or linkedin_url (up to 300) and returns name, title, employer and LinkedIn, or, from a profile URL, the work email. It costs $0.10 per call, charged only when a result is found. The People Data API page documents it as the route /api/hub/v1/people/enrich and the MCP tool person_enrich. Our person enrichment guide walks through the details.

Question	Use	Cost basis at BusinessMCP
What company is this?	Company lookup	$0.02 per found call
Who is this person?	Person enrichment	$0.10 per found call
What format do emails follow here?	Email pattern	$0.01 per found call

Key takeaway: ask the cheapest question that settles the decision. For many routing rules, company size and industry are enough, and the person lookup is optional.

Where reverse lookup fails

Expect misses, and plan for them.

• Personal webmail. A Gmail or Outlook consumer address has no employer in its domain, so business-contact providers have little to match on.
• Small or new companies. A store built from business contacts will not have everyone.
• Excluded regions. BusinessMCP never returns people located in the EU, EEA, UK or Switzerland, or people placed in California, Texas, Vermont or Oregon. Leads from those places will come back empty by design.
• Stale records. People change jobs. A title found today may be wrong in a year.
• Aliases and role addresses. Addresses like info@ or sales@ do not belong to one person.

Because of these misses, your routing logic needs a default path. When the lookup returns nothing, do not drop the lead; treat it as unknown and fall back to a form-based qualification question.

A simple inbound workflow

1. Normalise the email. Lowercase it, trim spaces and check for obviously disposable or personal domains.
2. Skip what cannot match. Do not spend on webmail addresses.
3. Look up the company first. If it is below your size threshold, route to self-serve and stop.
4. Enrich the person for the rest. Store name, title and the lookup date.
5. Route by role. Send senior buyers to a human quickly and others to nurture.
6. Log the purpose. Record why you ran the call, as the provider logs the declared purpose.

You can also use the opposite direction. If you have a name, the email finder goes from name to address, and our guide to finding a work email from a name and company covers the manual version.

Privacy and fair use

Enrichment creates a profile of someone who only gave you an email. Treat that carefully. Tell people in your privacy notice that you enrich lead data, store only what you use and delete what you do not need. Under the GDPR, personal data is any information relating to an identifiable person, so check the text on EUR-Lex and ask counsel about leads from Europe, even though BusinessMCP excludes those people from its results.

Prohibited uses matter too. BusinessMCP’s terms prohibit people data for credit, employment, insurance or housing decisions, so do not use enrichment to screen job applicants. Opt-outs are honoured: opted-out people are removed within about a day and never returned. If a lead asks you to delete their data, delete the enriched fields as well.

Measuring whether it helps

Compare lead response time, meeting-booked rate and cost per qualified lead before and after you add enrichment. If routing improves but cost per found record is high, tighten the rules about which leads get looked up. If hit rates are low in your market, say so in the vendor review. No accuracy figure is published for this endpoint, so your own numbers are the only evidence you have.

Cheaper ways to learn the same thing

Not every lead needs a paid lookup. Before you call an API, look at what you already have. The email domain often shows the company, the signature or form fields may include a title, and your own CRM may already hold the account. A short rules engine that checks these first can cut your lookup volume sharply.

For the account-level piece, BusinessMCP also offers a company lookup tool on its site, which is a quick way to check what kind of firm sits behind a domain before you decide whether a person-level lookup is worth $0.10. Treat any result as a lead for verification, not a fact, and confirm against the company’s own site when the stakes are high. Keep a note of which leads you skipped and why, so that you can review the rule later.

An example routing rule

Here is how the pieces fit in a simple, illustrative rule set. If the email is a personal webmail address, skip the lookup and ask a qualifying question in the reply. If the domain belongs to a company below your size threshold, route to self-serve. If it is above the threshold, enrich the person; when the title is senior, alert a human within the hour, and otherwise send to a nurture sequence. If the lookup finds nothing, mark the lead unknown and send the default qualifying question.

The rule has a deliberate shape: every branch ends in an action, including the branch where the data is missing. That matters because the provider may legitimately return nothing for leads in excluded regions or for people it does not hold. A pipeline that stalls when the lookup is empty will lose leads quietly, and you will not notice until the pipeline numbers look wrong at the end of the quarter.