Clean your Flodesk subscriber list
Export your Flodesk subscribers as a CSV, verify every address, then import the valid file back and keep the risky one out of your first send. Verification finds addresses that cannot receive mail. It cannot tell who has stopped reading, and an address it cannot confirm is called risky, never valid.
Export steps, bounce rules and prices read from Flodesk's own pages on 23 Oct 2026.
1. Export your Flodesk subscribers
- In Flodesk, go to Audience, then Segments.
- Hover over the All subscribers segment (or any segment), click the three dots in the top-right of its card and choose Download CSV.
- Flodesk emails the link to your login address. It expires after 24 hours, so repeat the steps if it lapses.
The file includes everyone currently in that segment, including unsubscribed, bounced and spam-marked contacts. Remove those before verifying.
2. What Flodesk already does with bounces
- Flodesk says it may pause an account automatically on high bounce or complaint rates, rejected emails, low engagement or suspicious activity. A paused account cannot send, and CSV uploads are not processed. (Flodesk help: account review overview)
- Its guidance on moving a list in says to exclude unsubscribed contacts, hard bounces and invalid addresses, and people who marked you as spam, before you upload. (Flodesk help: move your subscriber list)
Inactive is not invalid. A subscriber who has not opened for a year usually has a working mailbox, so verification keeps them. Deal with them separately: segment by last engagement, send a re-permission email, and remove the ones who do not answer. Verification is for the addresses that would bounce.
3. What verification can and cannot tell you
It can tell you
- The address is malformed or the domain has no mail servers.
- The mailbox does not exist, where the provider answers the check.
- The domain is disposable, which is common for junk signups.
- The domain accepts all mail, so the address cannot be confirmed.
It cannot tell you
- Whether the person reads your issues.
- Whether they agreed to hear from you.
- Whether the address is a spam trap.
- Whether a risky address is real. Providers that hide mailbox status and catch-all domains stay unconfirmed.
Unconfirmed always means risky, never valid. You get three files back, valid, risky and invalid, with your original Flodesk columns kept.
4. Import the clean file back
- Import the valid file as your active list. Keep the original columns so tags, names and signup dates survive.
- Do not re-import the invalid file. Addresses the platform already suppressed stay suppressed, and re-adding dead ones only brings the bounces back.
- Hold the risky file out of the first send. Mail it later, to the most engaged people first, and watch the bounce rate on that send.
- Flodesk's importer needs a CSV under 10 MB with empty rows and columns removed, and it detects duplicates and invalid addresses on upload. Split a big file into parts.
Flodesk bounce rate limits
Flodesk does not publish a bounce-rate number. It says a spam complaint rate of 0.30% or higher can lead to deliverability problems or suspended sending. Source: Flodesk help: avoid being marked as spam, read 23 Oct 2026. Other platforms' published lines are in bounce rate limits by platform.
How much is a dirty Flodesk list costing you?
Enter your own numbers. The share of dead addresses is your estimate (your last bounce rate is a floor, since only some dead addresses have bounced yet). Nothing is sent anywhere.
Invalid or abandoned, your best estimate.
From your invoice.
Fill in the list size and the share of dead addresses to see the result.
Flodesk's pricing page prices paid plans by subscriber count. The way the tiers read on the page is ambiguous between monthly and annual, so enter what your invoice says. Flodesk pricing, read 23 Oct 2026. Prices change; check the page before you decide.
Check a Flodesk address, then your list
Type any address. It gets the same check the paid plans run: syntax, the domain’s mail servers and, where the provider allows it, a live mailbox check. Nothing is sent to the address.
Five checks a minute, no account needed. Nothing is sent to the address — we ask its mail server whether the mailbox exists, then disconnect.
Have a list? Sign in with Google and the first 100 addresses are checked free, with results to download. No card.
By continuing you agree to our Terms and Privacy Policy.
Common questions
- How do I export my Flodesk subscribers?
- In Flodesk, go to Audience, then Segments. Hover over the All subscribers segment (or any segment), click the three dots in the top-right of its card and choose Download CSV. Flodesk emails the link to your login address. It expires after 24 hours, so repeat the steps if it lapses. The file includes everyone currently in that segment, including unsubscribed, bounced and spam-marked contacts. Remove those before verifying.
- What bounce rate does Flodesk allow?
- Flodesk does not publish a bounce-rate number. It says a spam complaint rate of 0.30% or higher can lead to deliverability problems or suspended sending. Source: Flodesk help: avoid being marked as spam, read 23 Oct 2026.
- Will verification find the inactive subscribers on my Flodesk list?
- No. Verification tells you whether an address can receive mail, not whether the person reads it. Someone who has not opened in a year can have a perfectly valid mailbox. Handle disengaged people with an engagement segment and a re-permission or sunset email, and use verification for addresses that are invalid or at risk of bouncing.
- What does a risky result mean?
- A risky address could not be confirmed as a real mailbox, usually because the domain accepts all mail (catch-all) or the provider will not say. An unconfirmed address is never reported as valid. Keep risky addresses out of your first send and mail them later, most engaged first.
- Is there a free way to try this on my Flodesk list?
- Yes. Sign in with Google and the first 100 addresses are checked free, with results to download and no card. After that, verification is $29.99 a month on the Pro plan.