A list is only as good as the data in it. Bad data means bounced emails, wrong contacts, and a sender reputation that degrades quietly in the background. Good data means your sequences reach real people at the right companies with working contact details.
List building is where we turn your ICP and account scores into an actual set of contacts we can reach.
Where we start
We do not buy a list. We build one from scratch using your ICP and scored account tiers as the input.
Every company in your tier one and tier two lists gets researched for contactable people matching the buyer profiles we defined in the ICP mapping stage. We are looking for the right title, the right seniority, and the right role within each account.
This takes longer than pulling a pre-built database export. It also produces a list that is actually worth sending to.
How we source contacts
We pull contact data from multiple providers rather than relying on a single source. Different providers have different coverage strengths depending on industry, geography, and company size. Using a waterfall approach means we get higher coverage and better data quality across the full list.
The sources we use most include Apollo, LinkedIn, Clay enrichment, Hunter, and several specialist providers depending on your specific market. We match across sources and take the highest quality record for each contact.
What we enrich every record with
For each contact we build a full record before they enter any sequence. This includes:
Verified work email
LinkedIn profile URL
Job title and seniority level
Company name, size, and industry
Direct dial where available
Any intent signals associated with their account
A contact without a verified email does not make it onto the active list. We flag those separately and attempt re-enrichment before marking them as unreachable.
The hygiene process
Once the list is built we run every record through a full hygiene pass before anything is sent.
Deduplication removes any contact that appears more than once across different sources or lists.
Normalisation standardises formatting across all fields so the data works cleanly inside your CRM and sequencing tools.
Domain validation checks that the company domain is active and not flagged as a known spam trap or honeypot.
Suppression checks cross-reference the list against any contacts who have previously opted out, unsubscribed, or been marked as do not contact.
By the time a contact enters a sequence, every record has passed all four checks.
How the list stays fresh
A list that is not maintained degrades quickly. People change jobs, companies get acquired, email addresses go stale. A contact who was accurate six weeks ago might bounce today.
We run a weekly refresh cycle on every active list. New contacts get added as accounts are updated. Bounced or undeliverable records get removed. Job change signals get flagged and the contact record gets updated to reflect the person's current role.
This is covered in more detail in the List Refresh article.
FAQ
How big will the list be?
It depends on the size of your target market and how tightly the ICP is defined. A well-scoped tier one list for most B2B companies sits somewhere between 200 and 800 contacts per ICP segment. We would rather have 400 highly accurate contacts than 4000 noisy ones.
Can we use an existing list we already have?
Yes. If you have an existing contact database we can run it through the same hygiene and enrichment process. We will tell you honestly what the quality looks like and what needs to be fixed before it is safe to send to.
What happens to contacts who bounce?
Bounced contacts are removed from the active list immediately and flagged in the data. We attempt re-enrichment to find an alternative email address. If none is found the contact is marked as unreachable and moved out of the active sequence pool.