Qualify B2B leads by email domain

Inbound forms collect a mix of buyers, students, job seekers, vendors and bots. The email address is the cheapest qualification signal you have, and it’s available the moment the form is submitted.

Signals that help qualify

Signal	Field	Reads as
Company domain	`category: "business"`	A company, even if it’s small
Personal provider	`category: "personal"`	An individual, or a buyer using a personal address
Disposable / relay	`is_disposable`, `is_relay`	Low intent, or someone avoiding follow-up
Education / government	`category`	Often a different sales motion
Role account	`is_role_account`	Shared inbox: real company, unknown person
Google Workspace / Microsoft 365	`workspace.*.detected`	Company size and stack hints; integration fit
Federated sign-in (Okta, ADFS…)	`workspace.microsoft_365.auth`, `identity_provider`	Usually a more mature IT setup
New or parked domain	`is_new_domain`, reason `parked_domain`	Brand-new company, or something less legitimate

These are hints, not firmographics. A two-person startup on Microsoft 365 looks similar to a large one. Combine them with your own data (company name, website, form answers).

A simple scoring sketch

function leadScore(v) {
  if (v.recommendation === 'block') return 0;
  let score = 50;
  if (v.category === 'business') score += 20;
  if (v.is_role_account) score -= 10;
  if (v.workspace?.microsoft_365?.detected || v.workspace?.google_workspace?.detected) score += 10;
  if (v.workspace?.microsoft_365?.auth === 'federated') score += 5;
  if (v.is_new_domain) score -= 15;
  return Math.max(0, Math.min(100, score));
}

Tune the weights against your own closed-won data; the point is to make the first sort automatic.

Where to run it

On form submission: HubSpot forms, Typeform, Webflow
In automation: Zapier, Make, n8n
In your backend: code examples

Check the domain instead of the address when you only need the company ({"domain": "acme.io"}); it works the same and keeps less personal data in flight.

Routing ideas

allow + score ≥ 70 → assign an owner immediately, notify in Slack
allow + lower score → nurture sequence with a meeting link
review → quick human look
block → newsletter or self-serve resources, not the sales queue