> ## Content Index > Fetch the complete content index at: https://www.millionverifier.com/llms.txt > Use this file to discover other available public pages before exploring further. # How to Verify Smartlead Leads Before Every Campaign - URL: https://www.millionverifier.com/blog/how-to-verify-smartlead-leads-before-every-campaign/ - Published: 2026-11-05T11:20:38.000Z - Updated: 2026-11-05T11:20:38.000Z - Author: Tamas Ham-Szabo **Verify Smartlead leads before every campaign, not once per list.** MillionVerifier connects to Smartlead directly with your Smartlead API key, so you can import leads, verify them and act on the results without exporting a CSV. Send to Good results, test Risky results in small batches, remove Bad results, and set Smartlead's High Bounce Rate Auto Protection low enough to catch a problem early. Good, Risky and Bad are MillionVerifier's verification results. Risky covers catch-all and unknown addresses. - **There is a native integration.** Some third-party guides say the two tools only work together through CSV files. MillionVerifier's help center documents a direct connection using your Smartlead API key. - **Smartlead's auto-pause reacts late early in a campaign.** It measures bounces against every lead in the campaign, not just the emails sent so far, so set a low threshold. - **Verify again before each new campaign,** even for leads you verified for an earlier one. ## Does MillionVerifier integrate with Smartlead? ![](https://www.millionverifier.com/content/images/2026/11/02-integration.png) Yes. Smartlead is one of MillionVerifier's ready-to-use integrations. You connect it with your Smartlead API key, import contacts from Smartlead for verification, and take action on the results from inside MillionVerifier ([Connect Smartlead with MillionVerifier](https://help.millionverifier.com/integrations/connect-smartlead-with-millionverifier?ref=millionverifier.com)). The CSV route still has a place: it's the right way to check leads before they go into Smartlead at all, as covered below. ## Why verify before every Smartlead campaign? ![](https://www.millionverifier.com/content/images/2026/11/03-why-every-campaign.png) Because lead data ages between campaigns, and Smartlead's own safeguards catch problems late. Three things to know: 1. **Leads go stale.** People change jobs and companies close their mailboxes. A lead that was fine for last quarter's campaign may bounce in this one. [Why Are My Apollo Emails Bouncing?](https://www.millionverifier.com/blog/why-are-my-apollo-emails-bouncing-how-to-verify-exported-leads/) covers how fast B2B data ages. 2. **Smartlead's Community Bounce filter only knows past bounces.** It removes addresses known to bounce from Smartlead's community bounce data ([Smartlead](https://helpcenter.smartlead.ai/en/articles/442-how-to-create-an-email-campaign-in-smartlead-the-new-version?ref=millionverifier.com)). That helps, but an address that has never bounced for anyone else gets through until it bounces for you. 3. **Smartlead's auto-pause measures against all leads, not emails sent.** High Bounce Rate Auto Protection pauses a campaign when it reaches the threshold you set ([Smartlead](https://helpcenter.smartlead.ai/en/articles/274-what-is-high-bounce-rate-auto-protection-in-smartlead?ref=millionverifier.com)). Smartlead calculates that rate as total bounces divided by the total number of leads in the campaign ([Smartlead](https://helpcenter.smartlead.ai/en/articles/210-bounce-autopause-and-webhook?ref=millionverifier.com)), so early in a campaign the real rate is much higher than the one being checked. Here's what that means in practice. A 2,000-lead campaign has sent its first 400 emails, and 20 have bounced. That's 5% of the emails sent, but only 1% of all leads. A 3% threshold won't fire until 60 bounces. Set the threshold to 1% and the campaign pauses at about 20 bounces, in this example right where the real problem shows up. ### What about Smartlead's own email verification? ![](https://www.millionverifier.com/content/images/2026/11/04-smartlead-verification.png) Smartlead sells email verification as an add-on, starting at 6,000 credits for $15\. It runs when you upload leads to a new campaign, and Smartlead notes that you can't verify leads once a campaign is live ([Smartlead](https://helpcenter.smartlead.ai/en/articles/196-how-to-verify-your-lead-list-using-smartlead?ref=millionverifier.com)). After verification, Smartlead sends to both valid and catch-all leads, according to its [feature announcement](https://vaibhavsmartlead.beehiiv.com/p/smartlead-inbox-intelligence-new-feature-release?ref=millionverifier.com). That's a reasonable first check. The workflow in this article differs in three ways: - **It works on leads already in Smartlead,** so you can re-check them before every new campaign, not only at upload. - **It keeps catch-all and unknown leads out of the main campaign** and sends them separately at a low daily limit. - **You don't pay for uncertain answers.** By default, MillionVerifier returns the credits for catch-all and unknown results, so you pay only for definite Good and Bad answers. ## How do you connect Smartlead to MillionVerifier? ![](https://www.millionverifier.com/content/images/2026/11/05-connect.png) Copy your API key from Smartlead and paste it into MillionVerifier. It takes about a minute: 1. **In Smartlead,** click your profile picture in the top right corner, open **Settings**, then **Your Profile**. 2. **Copy your API key.** 3. **In MillionVerifier,** choose Smartlead from the integrations and paste the key into the pop-up. You can add a comment to label the key. 4. **Click "Save and connect".** Treat the API key like a password: anyone with it can access your Smartlead account. You can remove the integration from MillionVerifier at any time. ## How do you verify a campaign's leads and act on the results? ![](https://www.millionverifier.com/content/images/2026/11/06-verify-and-act.png) Import the leads from Smartlead, verify them, and act on each result before the campaign sends. 1. **Click Verify on the Smartlead integration in MillionVerifier.** A pop-up shows what you can import from Smartlead and how many emails each one contains. 2. **Choose what to verify and click Import.** By default, you pay one credit for each Good or Bad result. Credits for catch-all and unknown results are returned automatically ([risky email credit policy](https://help.millionverifier.com/payments-credits/refund-for-risky-emails?ref=millionverifier.com)). 3. **Review the results.** You'll see the number and percentage of Good, Risky and Bad results. Catch-all resolution is already built into this check, so any catch-all address that still comes back Risky is one it couldn't resolve. 4. **Download the Risky and Bad reports.** 5. **Take the Risky and Bad leads out of the main campaign** before it sends, either with MillionVerifier's Smartlead actions or by removing them in Smartlead using the downloaded reports. 6. **Upload the Risky report as a new Smartlead campaign,** set up as described in the next section. What happens to each result: - **Good:** stays in the main campaign. - **Risky:** moves to its own low-limit campaign. - **Bad:** removed for good. For example, suppose a 2,600-lead campaign comes back with 2,240 Good, 250 Risky and 110 Bad results. The 250 Risky leads are 190 catch-alls that couldn't be resolved and 60 unknowns. You remove the 110 Bad leads and take the 250 Risky ones out of the main campaign. A day later, you re-check the 60 unknowns: 45 come back Good and go back into the main campaign, 5 come back Bad, and 10 are still unknown. That leaves 2,285 Good leads in the main campaign and 200 Risky leads for the separate one. ## How should you handle catch-all and unknown leads in Smartlead? ![](https://www.millionverifier.com/content/images/2026/11/07-catch-all-and-unknown.png) Resolve what you can, then send the rest from a separate campaign at a low daily limit. - **Catch-all leads:** catch-all resolution is already part of MillionVerifier's standard check. The [Catch-All Email Verifier](https://www.millionverifier.com/services/catch-all-email-verifier/) resolves 30% to 40% of catch-all addresses into Good or Bad, so the catch-alls that come back Risky are the ones it couldn't resolve. If most of a list sits on catch-all domains, verify it as a file with the Bulk Email Verifier, where these deeper checks have more time to finish. - **Unknown leads:** the receiving server didn't give a clear answer, often because it was slow or temporarily refusing connections. Verify them again a day or two later. By default, the first unknown result costs no credit, and the re-check uses one only if it returns a definite answer. - **Whatever stays Risky:** put it in its own Smartlead campaign, with a daily limit that keeps Risky leads to no more than 10% of each day's sends from the same mailboxes. In the example above, if the main campaign sends to 360 new leads a day, the Risky campaign gets a limit of 40\. That's 10% of 400 daily sends, and the 200 Risky leads go out over five days. Give the Risky campaign its own High Bounce Rate Auto Protection threshold of 3%. On 200 leads, that pauses it at the sixth bounce. A 1% threshold would pause it at the second, which on a catch-all segment means stopping almost at once. Bounces from catch-all domains can also arrive hours later as separate bounce emails, so check each day's results before the next batch goes out. If you have to choose between Risky leads, start with the ones whose address matches the company's known pattern, such as first.last@. [How to Handle Catch-All and Risky Emails](https://www.millionverifier.com/blog/how-to-handle-catch-all-and-risky-emails-without-ruining-deliverability/) covers the full method. ## What about leads that aren't in Smartlead yet? ![](https://www.millionverifier.com/content/images/2026/11/08-leads-not-in-smartlead.png) Verify the file before you upload it. That way, Bad addresses never become leads in the first place. 1. **Run the CSV through the** [**Bulk Email Verifier**](https://www.millionverifier.com/services/bulk-email-verifier/)**.** 2. **Split the results.** Good results go into the main campaign file, Risky results into a separate file for the low-limit campaign, and Bad results are dropped. 3. **Check your columns before you import.** Make sure each file still has the fields your sequence uses, such as first name and company, and map them when you upload to Smartlead. This is the right route for fresh exports from a lead database. For Apollo exports specifically, see [Why Are My Apollo Emails Bouncing?](https://www.millionverifier.com/blog/why-are-my-apollo-emails-bouncing-how-to-verify-exported-leads/) If you run campaigns for clients, [How Lead Gen Agencies Protect Client Domains with Bulk Email Verification](https://www.millionverifier.com/blog/how-lead-gen-agencies-protect-client-domains-with-bulk-email-verification/) covers the agency side. ## Frequently asked questions #### Does MillionVerifier integrate with Smartlead? Yes. You connect the two with your Smartlead API key, import leads from Smartlead into MillionVerifier for verification, and act on the results without exporting a CSV. #### Doesn't Smartlead already filter bad emails? Partly. Smartlead's Community Bounce feature removes addresses known to bounce from its community data, and Smartlead sells an email verification add-on that runs when you upload leads to a new campaign. Smartlead's verifier can't check leads once a campaign is live, and it sends to catch-all leads along with valid ones. Verifying with MillionVerifier before each campaign lets you re-check leads you already have and keep catch-alls in a separate campaign. #### What bounce threshold should I set in Smartlead? Set High Bounce Rate Auto Protection to 1% for your main campaign. Smartlead calculates the rate against every lead in the campaign, not just the emails already sent, so a higher setting reacts late in the early days of a campaign. For a separate campaign of Risky leads, use 3%, so it doesn't pause at the second bounce. #### How often should I verify Smartlead leads? Before every campaign, including leads you verified for an earlier one. Re-check unknown results a day or two later before you send to them. #### Can I send to catch-all leads in Smartlead? Yes. MillionVerifier already resolves part of the catch-all segment during verification. Send the catch-alls it couldn't resolve from a separate campaign, with a daily limit that keeps them to no more than 10% of each day's sends. #### How much does it cost to verify Smartlead leads? By default, one credit for each Good or Bad result. Credits for catch-all and unknown results are returned automatically. A free MillionVerifier account comes with 100 credits to test the integration. ## Verify your next Smartlead campaign Smartlead's auto-pause tells you when a campaign has already gone wrong. Verification stops it going wrong in the first place. Connect Smartlead to MillionVerifier, verify your next campaign's leads before it sends, and keep your mailboxes out of trouble. [Create your free account](https://app.millionverifier.com/register?ref=millionverifier.com) to get 100 free credits, no credit card needed. --- [Create Your Free Account Now](https://app.millionverifier.com/register?ref=millionverifier.com) --- Why Choose Millionverifier ![99%+ Accuracy Rate](https://www.millionverifier.com/content/images/2026/06/accuracy_rate_hero-1.webp) We have kept improving our email verification software for over six years now, and we are incredibly proud of our outstanding 99%+ email verification accuracy. [99%+ Accuracy Rate](https://www.millionverifier.com/why-millionverifier/accuracy-rate) ![Best Email Verification Prices](https://www.millionverifier.com/content/images/2026/06/best_email_verification_prices_hero-1.webp) We have created MillionVerifier to provide the best email verification service possible for email marketers with higher email verification needs. [Best Email Verification Prices](https://www.millionverifier.com/why-millionverifier/best-email-verification-prices) ![Excellent Verification Service](https://www.millionverifier.com/content/images/2026/06/excellent_email_verification_service_hero--2-.webp) Our customers love what we do. We work hard to deliver the best results and user experience for our customers. [Excellent Verification Service](https://www.millionverifier.com/why-millionverifier/excellent-email-verification-service)