Build a Suppression List From Smartlead Before You Reuse Leads or Switch Tools

Download the campaign's Lead list and its bounced Inbox view, export the Global Block List, put everyone who bounced, unsubscribed, replied or said no into one suppression file, and import it back into Smartlead's Global Block List with the right client attached. What's left, completed leads who never answered, is the reusable part. Check it live before the next campaign.

This matters when you recycle old leads into a new angle, when an agency moves a client to a new workspace, and when you move from Smartlead to another sequencer. In every case the opt-outs and bounces sit inside the old tool. Our cold email suppression list post covers the master list and the legal deadlines. This post covers the Smartlead export and split.

The two Smartlead exports

Smartlead's data export guide describes two campaign-level downloads:

Export	Where	Filters	What it tells you
Lead data	Campaign > Lead list > Filter > download CSV	Email status (Not contacted yet, In progress, Completed, Stopped), lead category	Where each lead ended up, and how replies were categorised
Inbox data	Campaign > Inbox > Filter > download CSV	Sequence step; Opened, Clicked, Replied, Unsubscribed, Bounced	Lead email, sent and reply times, reply message, Is Unsubscribed

For bounces, Smartlead's bounced data guide says: open the campaign, go to Inbox, filter by Bounced, download as CSV. Take both exports for every campaign you plan to reuse.

Which leads go where

Smartlead value	List	Why
Bounced (Inbox filter or is_bounced)	Suppression	The address failed
Unsubscribed / Is Unsubscribed	Suppression	They asked you to stop
Blocked status, Do Not Contact category	Suppression	Already blocked for a reason
Interested, Meeting Request, any reply count	Suppression (handle by hand)	Past the cold stage
Not Interested, Wrong Person	Suppression	They answered no
Completed or Stopped with no reply	Reusable	Check live first
Out of Office	Reusable	They didn't answer you

Split the file

1. Upload the Lead list export, and the Inbox exports if you took them, to the Smartlead leads to email list tool. Paste several campaigns one after another; repeats merge and the strongest reason to suppress wins.
2. Leave replied and not-interested set aside unless you have a reason to keep them.
3. Download two files: reusable leads and suppression.
4. Add your Global Block List export to the suppression file. The suppression list merger combines and dedupes several lists into one.

Smartlead doesn't publish its CSV headings, so the tool finds the status, category and unsubscribe columns by name. Check the notes above the result to see which columns it found.

Load it into the Global Block List

From Smartlead's Global Block List guide:

• Import: on the Global Block List page, open the dropdown next to Add Block List and choose Import CSV File. The file can hold emails or domains.
• Domains vs emails: a domain such as abc.com blocks every address at it; a full email blocks only that person.
• Uploads after the block: Smartlead says new lead lists uploaded to any campaign skip addresses already on the list.

Two rules make blocks silently miss. Smartlead's troubleshooting article gives both:

1. Client association. A block only applies when the campaign and the block entry share the same client. An entry with no client only covers campaigns with no client. An agency that wants a lead blocked for three clients needs three entries.
2. Domain format. Smartlead matches domains exactly. Enter domainname.com, not https://www.domainname.com.

The same article warns that removing a lead from the block list deletes that lead's email thread, and the thread can't be recovered. Export first if you might need it.

If you prefer the API, Smartlead's block list endpoint accepts a list of emails or domains with an optional client ID. Our post on verifying Smartlead campaign leads through the API covers the rate limits that apply when you write back in bulk.

Load it everywhere else

The block list only protects Smartlead. Import the same suppression file into your CRM and any other sending tool, and keep the master copy outside all of them. If you're moving to lemlist or Instantly, our lemlist and Instantly suppression list post shows where each one takes a blocklist file.

Check the reusable leads

A lead that completed a sequence in the summer didn't bounce then. Since then some of those people will have changed jobs, and their work inboxes will have closed.

1. Upload the reusable file at /verify. Every address gets a live mailbox check. Valid, risky and invalid download as separate files, and catch-all domains are marked.
2. Import only the valid file into the new campaign. Put catch-all leads in a smaller, slower campaign, or drop them.
3. Keep an eye on the first few days. Our Smartlead bounce rate post explains how Smartlead counts bounces and when it pauses a campaign.

If you'd rather check leads where they already sit, cleaning a Smartlead campaign in place shows how to do it without exporting.

What the exports miss

• Column names aren't published. Check which columns the tool found.
• Leads deleted from a campaign aren't in its export. If you deleted bounces in the past, the Global Block List export is your only record of them, if they were blocked at all.
• Replies outside Smartlead. People who answered a different inbox, or asked your CRM to stop, need merging in separately.

Where SimpleVerifier fits

The Smartlead export tool is free and runs in your browser. Nothing is uploaded until you choose to check the addresses. The live check is the paid part: the first 100 checks are free with a Google sign-in on the verify page. Pro is $39 a month with the first 100,000 checks a month at full speed, then slower, never cut off, and one-time packs of 10,000 checks for $15 never expire. See pricing.