Email data append: add an email address to a name and postal address

Email Data Append takes a person's name and postal address and returns the email address on record for them. Use it when your list has offline contact details but no way to email anyone on it.

What it tells you

• Whether the person you described was matched to a record.
• The email address tied to that name and postal address.
• A clear no-match answer when nothing lines up, rather than a silent blank.
• The credits used on the call and your remaining balance.

What you need to provide

All five of these, sent inside the input object:

• First name of the contact.
• Last name of the contact.
• Street address.
• City.
• ZIP code.

What it costs

10 credits per lookup. Live per-product costs are shown on the Billing page in your dashboard.

How to run it

• In the dashboard: Email Data Append
• From your code: POST /v1/email-append, then see the Developer Hub at app.1lookup.io/developer-hub.

Good to know

• Results are point-in-time. People move and change email addresses, so a match reflects the record as it stood when you ran the lookup.
• Every one of the five inputs is required, so a row missing a ZIP code or a street address cannot be run as is. Fill the gap or leave that row out.
• Not every name and address has an email on record. A no-match is a normal outcome, not an error.
• If you have the email address and want the person behind it, use Reverse Email Lookup instead.
• Names, postal addresses and email addresses are personal data. Use them for legitimate business purposes only.

Updated on: 24/08/2026