Reputation Builder
Bounce rate auto-pause
Inbox Boost can automatically pause warmup when bounces exceed a percentage you set. This guide explains the threshold input, how the rate is measured, and what happens in common scenarios.
Where to find this setting
Open Reputation Builder → Inbox Boost, select your domain, and go to Edit setup. Under Auto-pause on high bounce rate, you configure:
- Toggle — turn auto-pause on or off
- % bounce rate threshold — the single number input (e.g.
5or10) - Measure bounce rate — Today only or Entire warmup
- Apply threshold change — Today only or All future days (shown when you are bounce-paused or changing the limit during active warmup)
The Overview tab also shows a Bounce guard panel when warmup paused because of bounces, including the current rate and effective threshold.
Default: 5%
New domains start with a 5% bounce rate threshold unless you change it during setup. Turning the auto-pause toggle off saves 0, which disables bounce auto-pause entirely.
Auto-pause only runs after at least 5 sends are included in the measured window (so a single early bounce does not pause warmup immediately).
The threshold input (one number box)
The input is always the same thing: pause warmup if bounce rate goes above this percentage.
| Value you enter | Meaning |
|---|---|
5 | Pause if bounce rate exceeds 5% (recommended starting point) |
10 | More tolerant — pause only above 10% |
0 (toggle off) | Never auto-pause for bounce rate |
Example: threshold 5, 100 sends today, 6 bounces → rate is 6% → warmup auto-pauses.
Two separate choices (do not confuse them)
These answer different questions:
| Setting | Question it answers |
|---|---|
| Measure bounce rate | How is the percentage calculated? (today's mail only, or all mail since warmup started) |
| Apply threshold change | How long does the number in the input box apply? (just today, or your new permanent default) |
Measure bounce rate: Today only
Formula: bounces today ÷ sends today × 100 (using your domain's send timezone).
- Resets each local send day at midnight in your chosen timezone
- Yesterday's bounces do not affect today's rate
- Best for most users
Measure bounce rate: Entire warmup
Formula: all bounces since warmup started ÷ all sends since warmup started × 100.
- Does not reset at midnight
- One bad day keeps affecting the cumulative percentage until you restart warmup
- Stricter — useful when you want cumulative reputation protection
Apply threshold change: Today only
The value in the input box (e.g. 10) is a temporary override for the current local send day only. Your saved default (e.g. 5) returns at the next local midnight.
Use this when warmup paused for bounces and you need a higher limit to resume today without keeping that higher limit tomorrow.
Apply threshold change: All future days
The value in the input box becomes your permanent default until you change it again.
Four common configuration scenarios
Below, assume the threshold input is 10 (10%). These match the combinations you can select in Edit setup.
Scenario 1 — Entire warmup + All future days
| Setting | Value |
|---|---|
| Threshold input | 10% |
| Measure | Entire warmup |
| Apply | All future days |
Behavior: Bounce rate is cumulative for the whole warmup run. 10% is your permanent limit. Example: 500 total sends and 40 total bounces → 8% (OK). If bad mail pushes you to 11% overall → auto-pause.
Good for: strict, long-term reputation guardrails.
Scenario 2 — Today only + All future days
| Setting | Value |
|---|---|
| Threshold input | 10% |
| Measure | Today only |
| Apply | All future days |
Behavior: Each day starts fresh for the rate calculation. 10% is your default every day. Example: today 100 sends, 8 bounces → 8% (OK). Tomorrow: 0 bounces counted for rate purposes, threshold still 10%.
Good for: normal daily monitoring with a fixed limit (common default-style setup, but with 10% instead of 5%).
Scenario 3 — Today only + Today only
| Setting | Value |
|---|---|
| Threshold input | 10% |
| Measure | Today only |
| Apply | Today only |
Behavior: Rate is calculated from today's sends only. 10% applies only today. At the next local midnight, the bounce count resets and the threshold returns to your base default (e.g. 5%).
Example (recovery): Paused at 20% today (2 bounces / 10 sends). Set threshold to 25, choose Today only for both measure and apply, save, then Resume. Sending continues today. Tomorrow: fresh day, threshold back to 5%.
Good for: temporary relief after a bounce spike without keeping a high limit forever.
Scenario 4 — Entire warmup + Today only (avoid this combination)
| Setting | Value |
|---|---|
| Threshold input | 10% |
| Measure | Entire warmup |
| Apply | Today only |
Behavior: The rate stays cumulative (does not reset at midnight), but the threshold drops back to your base default (e.g. 5%) tomorrow.
Example problem: Day 1: 10 sends, 2 bounces → 20% cumulative → paused. You raise the limit to 25% (today only) and resume. Next day: threshold returns to 5%, but cumulative rate is still 20% → Resume may be blocked even if you had zero new bounces today.
Recommendation: If you measure Entire warmup, use All future days for the threshold. Do not combine entire-warmup measurement with a today-only threshold override.
Recommended starting setup
| Setting | Recommended value |
|---|---|
| Auto-pause toggle | On |
| Threshold input | 5 |
| Measure bounce rate | Today only |
| Apply threshold change | All future days |
Recovering after bounce auto-pause
- Open the domain Overview tab — read the pause reason and Bounce guard stats (current rate, effective threshold, base default).
- Fix the underlying issue if you can (DNS, list quality, invalid recipients on seeds, etc.).
- Go to Edit setup. Raise the threshold input to a value above your current bounce rate (e.g. rate is 20% → enter at least
21or higher). - Choose Measure: Today only and Apply: Today only if you only need to finish today; otherwise use All future days if you want the new limit permanently.
- Save settings, then click Resume on Overview.
Resume is blocked if the bounce rate is still above the effective threshold — raise the limit first, then resume.
What resets at a new local send day
| Item | Today only measure | Entire warmup measure |
|---|---|---|
| Bounce count used for rate | Resets (fresh day) | Does not reset |
| Today-only threshold override | Cleared — base default applies | Cleared — base default applies |
| Permanent default threshold | Unchanged | Unchanged |
What auto-resumes vs stays paused
At local midnight, warmup does not automatically resume for most pause reasons. You resume manually when ready.
| Pause reason | Auto-resume at new local day? |
|---|---|
| Plan daily send limit reached | Yes — resumes when the new day's quota is available |
| Bounce rate exceeded | No — you must review, adjust threshold if needed, and click Resume |
| Manual pause (you clicked Pause) | No |
| DNS no longer verified | No — fix DNS first |
Alerts
When bounces occur during warmup, SenderSignal can alert your team (email, Slack, webhook depending on your alert configuration):
- Individual bounce — each bounced warmup message
- Threshold exceeded — when auto-pause triggers because the rate crossed your limit
Quick reference
INPUT BOX → Pause when bounce rate goes above this % MEASURE → Count bounces from today only, or from whole warmup? APPLY → Is this % just for today, or my new permanent default? Default threshold: 5% Minimum sends before auto-pause: 5 Disable auto-pause: turn toggle off (saves 0%)