SimpleVerifier Team · Reviewed
How many bounces are too many?
Aim to keep hard bounces under 2% of each send. Published enforcement lines are higher, but they are where sending stops: Brevo can suspend above 2%, HubSpot and Amazon SES review accounts at 5%, and SES may pause sending at 10%. Mailchimp and Mailgun enforce thresholds they do not publish.
The published lines
These come from each vendor's own help pages, read on 1 October 2026. A benchmark is advice; an enforcement line is where sending actually stops.
- Brevo: hard bounce rate above 2% can lead to suspension.
- HubSpot: a hard bounce rate of 5% in a month can lead to suspension.
- Amazon SES: 5% puts an account under review; 10% or more may pause sending.
- Postmark: bounce rate must stay below 10%.
- Instantly: campaigns auto-pause at 5% by default after 200 or more sends (adjustable).
Why a 2% target
A sender is judged on the whole stream, so one bad segment can push the total over a line. Keeping the overall target at 2% leaves room for a segment that bounces at 5% or more. Count hard bounces (permanent failures such as an unknown mailbox) separately from soft bounces, which are temporary.
What SimpleVerifier costs and what it cannot confirm
- What it is
- Email verification with a real SMTP mailbox check: each address comes back valid, risky or invalid with a reason. Includes an email finder on Pro and up.
- Price per check
- Starter $9/mo for 2,500 ($3.60 per 1,000); Pro $39/mo, 100,000 a month at full speed ($0.39 per 1,000 when used), then slower, never cut off. Business $99/mo with 300,000 at full speed; Agency $249/mo with 750,000 at full speed.
- One-time packs
- 10,000 for $15 ($1.50 per 1,000); 25,000 for $29 ($1.16 per 1,000); 50,000 for $49 ($0.98 per 1,000); 100,000 for $79 ($0.79 per 1,000); 250,000 for $169 ($0.68 per 1,000). Credits never expire, run at standard speed, CSV verification only (no API or finder).
- Free checks
- First 100 email checks free with a Google sign-in, no card, once per account. Single checks on the free email checker need no account.
- Billing
- Monthly subscription, cancel anytime (yearly billing optional). One-time packs are listed above. Starter allowances reset monthly and do not roll over.
- Speed today
- One sending IP today, shared by every customer: about 13,000 mailbox checks a day in the standard lane. Bad syntax, dead domains and disposable addresses return at once; a list of 100,000 takes days, not hours, and each job shows its estimated finish time.
- Catch-all handling
- Catch-all (accept-all) addresses stay risky, never valid, and are graded higher, medium or lower likelihood with the reasons. Anything a mail server does not confirm is risky.
- API and MCP
- REST API on Pro, Business and Agency (Pro includes 10,000 calls a month, then $1.50 per 1,000). Remote MCP server with 6 tools for Claude, ChatGPT, Cursor and VS Code. No API on Starter.
- Integrations
- Connects to Instantly, Smartlead, HubSpot and Mailchimp by API key: verifies a campaign or list and tags each contact with its result. CSV in and out for any other tool.
- Phone
- Free phone format checks (country, type range). Live carrier and line-type lookups come with Pro + Phone at $49.99/mo (5,000 a month). It never says a number is in service.
- What it does not do
- No sending, warmup or inbox placement tests. No published accuracy benchmark against other verifiers. Catch-all domains, Yahoo and AOL cannot be confirmed, and Outlook.com and Hotmail mailboxes are not probed while Microsoft refuses checks from our server's network: all of these come back risky, never valid.
SimpleVerifier facts from our pricing page and product. Last updated .
Related questions
- Is a 3% bounce rate bad?
- It is below most published enforcement lines but above Brevo's 2% suspension line. Treat anything over 2% as a list-quality problem to fix before the next send.
- What should I do when bounces spike mid-campaign?
- Pause the campaign, export the bounced addresses, suppress them, verify the rest of the list, and resume with a smaller batch.
Sources
- Bounce limits by platform, read from each vendor's own docs (SimpleVerifier, 1 Oct 2026)
- Amazon SES enforcement FAQ
- HubSpot: why is my email suspended
Figures marked as ours come from SimpleVerifier’s own dated tests on made-up addresses, published with their data on the research page. No customer data is used, and we publish no accuracy percentage because we have no independent measurement to back one.
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