What is Deliverability Score?
A deliverability score is a rating that predicts how likely an email is to successfully reach the recipient's inbox rather than being filtered to spam or bounced.
Deliverability Score, explained
A deliverability score is a metric used to assess the likelihood that an email will be successfully delivered to the intended recipient's inbox. This score can apply at two levels: the sender level (how healthy is your sending domain and IP reputation) and the recipient level (how likely is this specific email address to accept and receive your message).
At the sender level, deliverability scores are influenced by factors including bounce rate history, spam complaint rate, authentication setup (SPF, DKIM, DMARC), sending volume consistency, engagement rates from previous campaigns, and blacklist status. Email service providers like Google and Microsoft track these signals to determine whether to deliver your emails to the inbox, route them to spam, or reject them outright.
At the recipient level, a deliverability score evaluates the quality of individual email addresses. This includes whether the address is verified as valid, whether it is on a known spam trap list, whether the domain is configured to receive email, whether the address is role-based (like info@ or support@), and whether the domain is catch-all. These factors help predict whether a specific email will bounce, land in spam, or reach the inbox.
Maintaining high deliverability is critical for B2B outbound and marketing teams because the consequences of poor deliverability extend beyond individual emails. When your bounce rate climbs above 2-3%, email providers begin throttling or blocking your messages across the board. This means even your legitimate one-to-one sales emails can end up in spam, affecting the entire organization's ability to communicate with prospects and customers.
Cleanlist AI contributes to deliverability management by providing recipient-level scoring during its email verification process. Each email address receives a deliverability assessment based on verification status, catch-all detection, role-based identification, and historical patterns. Teams can use these scores to segment their lists by deliverability risk, sending only to high-confidence addresses in volume campaigns and handling risky addresses through lower-volume, more targeted channels. This proactive approach prevents the bounce rate spikes that damage sender reputation.
Expert definition
“A deliverability score is a probability estimate that an email will reach the inbox, calculated from sender-side reputation signals (bounce rate, complaint rate, SPF, DKIM, DMARC, sending consistency) and recipient-side risks (catch-all, role-based, spam-trap exposure). Email teams, lifecycle marketers, and outbound SDR ops live and die by it. The buried truth is that since Google and Yahoo's February 2024 bulk-sender rules took effect, anything below a 0.3% complaint rate is mandatory and authentication is no longer optional, domains without DMARC are getting silently throttled in 2024 and 2025. Inbox placement above 85% is the working benchmark for healthy B2B sending, and dropping below 80% generally means you have a list-quality problem rather than a content problem.”
References & Sources
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Frequently asked questions
Short answers about Deliverability Score, in plain English.
All glossary termsWhat factors affect email deliverability score?
Key factors include bounce rate, spam complaint rate, email authentication setup (SPF, DKIM, DMARC), sending volume and consistency, list quality, engagement rates (opens, clicks), blacklist status, and the content of your emails. At the recipient level, whether the address is valid, role-based, catch-all, or on a spam trap list also impacts deliverability.
What is a good email deliverability rate?
A good email deliverability rate is 95% or higher, meaning at least 95% of your sent emails reach the recipient's mailbox (inbox or spam folder). Inbox placement rate - the percentage that lands in the primary inbox rather than spam - should ideally be above 85%. Bounce rates should stay below 2% and spam complaint rates below 0.1% to maintain strong sender reputation.
How can I improve my deliverability score?
Verify all email addresses before sending, maintain consistent sending volumes, properly configure SPF/DKIM/DMARC authentication, remove unengaged contacts from lists, honor unsubscribes promptly, and avoid spam trigger words in content. Cleanlist AI helps by pre-verifying addresses and flagging risky emails before they enter your sending pipeline, keeping your bounce rates low and sender reputation intact.
Put Deliverability Score to work in Cleanlist AI
Cleanlist AI can verify the deliverability of your whole list across 25+ providers: 98% verified work emails and 85% phone numbers on the 500-lead benchmark, with the Research and Qualification skills on every row. Clu turns the job into an agent that runs every week, adds the people to your sequences and posts each run to Slack. 14 days of Pro, free: 250 credits, 3 seats, agents, Sequences and Clu in Slack.
A demo of Clu, the Cleanlist AI agent, doing this for a whole list. Asked: Verify every email in Series B sales leaders before Monday's send. Clu runs the tools, asks for confirmation before spending credits (Validate 480 emails on Series B sales leaders, 240 credits), fills the list row by row and reports: 480 checked: 431 verified, 33 risky, 16 invalid. Want me to drop the invalid ones before Monday?
Describe the job once. An agent runs it every week.
Clu turns one sentence into an agent. It searches 1B+ profiles, finds verified emails and phone numbers across 25+ providers, adds the people to your sequence and posts each run to Slack.
Weekly ICP outbound
Built by Clu from: “Every week, find 500 new people who match my ICP, get their emails and phones, and add them to Series B outbound.”
- Searched 1B+ profiles for new ICP matches500 foundPeople Search
- Ran the waterfall across 25+ providers487 emails · 412 phonesWaterfall
- Verified every email and phoneSMTP + catch-allVerification
- Added them to Series B outbound500 peopleSequences
- Posted the run to #pipelineSlackAgents
Friday 4:52 PM15 replies · 5 calls booked
Everything in the 14-day Pro trial
- Clu and agentsDescribe the job in one sentence. Clu builds the agent, runs it on a schedule or a CRM trigger and posts every run to Slack.
- People and Company SearchFind your buyers in 1B+ profiles from one sentence. Searching costs 0 credits.
- Waterfall enrichmentAsk 25+ providers in order and stop at the first verified email or phone number. 98% verified work emails and 85% phone numbers on a 500-lead benchmark.
- Email verificationRun SMTP and catch-all checks on every address before it reaches a sequence, at half a credit an email.
- ICP scoringScore every lead 0 to 100 against your ICP, with the reasons written down. The Research and Qualification skills do the digging.
- SequencesSend email from your reps' own inboxes, with LinkedIn steps and call tasks. A reply stops the sequence. Sending costs 0 credits.
- CRM syncTwo-way sync with HubSpot, Salesforce and Pipedrive. Push finished lists to Outreach, Salesloft and Lemlist.
- Chrome extensionGet a verified email and phone number in one click on LinkedIn, Sales Navigator, Salesforce and HubSpot.
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14 days of Pro, free: 250 credits, 3 seats, agents, Sequences and Clu in Slack. Then Free at 50 credits a month, or Starter at $49 and Pro at $89 a seat a month.
Where to next
Related terms
- Email VerificationEmail verification is a 4-step deliverability check (syntax, MX, SMTP handshake, risk flags) that confirms an address can receive mail without sending anything. Full verification catches 95-99% of bad addresses; syntax-only checks catch 70-90%.
- Email Bounce RateEmail bounce rate is the percentage of sent emails that were not delivered to the recipient's inbox, calculated by dividing the number of bounced emails by the total emails sent.
- Catch-All EmailA catch-all email domain is configured to accept all incoming messages regardless of the specific address, making it impossible to verify whether a particular mailbox exists.
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