Projected end-of-month list size
Advanced but practical: model list growth with inflow and churn in separate steps, like lifecycle teams do.
Example scenario
A home goods brand starts the month with eighteen thousand four hundred marketable subscribers after hard-bounce scrubs and counts ninety-eight thousand qualified sessions hitting popup plus footer capture surfaces tied to GA4’s hostname filter. Two point six percent of those sessions consent through double opt-in flows while legacy twelve-month cohort churn implies one point two percent of current subscribers unsubscribe within the month before win-back mail fires. Netting acquisition minus churn yields about two thousand five hundred forty-eight fresh subscribers and roughly two hundred twenty-one departures, projecting nearly twenty thousand seven hundred twenty-seven subscribers at month-end—capacity planners compare that delta against ESP tier breaks before approving SMS bridge experiments.
Projected end-of-month list size
Current list + new subs - unsubscribes
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How to run the email list growth forecast wizard
- On the list-base step, input current subscribers from your ESP’s marketable count—suppressed hard bounces, globally unsubscribed profiles, and GDPR deletes excluded—matching the audience eligible for promotional sends.
- On acquisition, input monthly visitors to capture paths only when opt-in rate references those surfaces; if analytics counts whole-site sessions, narrow with landing filters or adjust opt-in rate downward so traffic denominators align.
- Slide opt-in rate (%) using trailing-thirty confirmed joins divided by eligible sessions or popup impressions—keep SMS keyword joins out unless visitors includes SMS capture.
- On churn, slide monthly unsubscribe rate (%) using unsubscribes divided by starting list size for the month; read projected subscribers plus extra outputs for new subscribers and expected unsubscribers before booking creative tests against ESP billing tiers.
House-list acquisition & churn planning ranges
- Sitewide email capture rate on commerce traffic (popup plus embedded forms, blended)
- Often ~1–4% depending on incentive depth, mobile UX, and checkout-login duplication controls
- Monthly list churn via unsubscribes alone (healthy permissioned retail lists)
- Commonly sub-two percent per month before adding spam complaints and dormant pruning policies
- Double opt-in adoption among GDPR-conscious EU-heavy brands
- Confirmed opt-in workflows intentionally reduce counted subscribers while lifting engaged denominator quality
Best use cases
- Forecasting and scenario planning
- Client education and pre-qualification
- Budget and performance decision support
Frequently asked questions
Why does churn multiply current subscribers instead of projected subscribers mid-month?
This wizard applies a simple monthly coefficient like finance snapshots—linear approximation before sophistication. If cadence spikes mid-month, advanced teams average daily balances or stage recurring cohort churn separately; swap constants accordingly rather than expecting ESP exports to match accounting-grade retention curves.
Should monthly visitors include logged-in checkout accounts that never see popups?
Only if your opt-in numerator counts joins from those journeys. Mixing full-site sessions with popup-only conversions dilutes opt-in rate—either restrict visitor counts to capture-eligible paths or rebuild opt-in rate as joins divided by popup impressions.
Double opt-in confirmations lag two weeks—does that bias new subscribers?
Yes when confirmations arrive next month. Align measurement windows—often trailing sixty-day rolling join rates—or delay counting joins until confirmation timestamps land inside the forecast month so acquisition math matches ESP reality.
Do I subtract spam complaints and recurring dormant suppressions from list base?
Treat them consistently: if compliance scrubs fire automatically, incorporate them into unsubscribeRatePct or shrink current subscribers before running the wizard. Splitting passive churn from explicit unsubscribes keeps leadership aligned with deliverability dashboards.
Glossary
Scenario modeling
Testing multiple assumptions to estimate possible outcomes before execution.
Commercial intent
User behavior indicating readiness to buy, subscribe, or request a quote.
Related calculators
Category: Email marketing & audience forecastingTopics: List growth modeling, Subscriber churn, Opt-in funnel planning
Last reviewed: 2026-05-07
Reviewed by: Calclet Growth Team