Warmerly
An email digest, at most one a day; health webhooks on the Agency plan; no Slack alert found.
Warmerly
Mailreach
One-to-one · Alerts
Alerts
One row, in depth: what each tool does, the verified numbers, and who each suits.
Mailreach details read from its pricing page and script, home page, product pages, terms, privacy policy and docs on 21 October 2026.
Warmerly
An email digest, at most one a day; health webhooks on the Agency plan; no Slack alert found.
Mailreach
Slack or webhook alerts when reputation scores change and on automatic spam tests.
The short answer
Alerts, in one look.
Warmerly sends an email digest, at most one per user a day, and signed health webhooks on the Agency plan only, with no Slack alert found, while Mailreach sends Slack or webhook alerts when a reputation score changes. Mailreach is ahead on channels. Last checked 22 October 2026.
MailreachMailreach ahead on this row
Slack or webhook alerts when reputation scores change and on automatic spam tests.
The picture
Drawn side by side.
From a change to your eyes
As each describes it
WarmerlyMailreach
Warmerly
Check runs every 15 minutesAlert raisedOne email digest a day
Mailreach
Reputation score changesAlert sentSlack or webhook
Warmerly's webhooks, for score drops and DNS changes, need the Agency plan. We found no Slack alert in Warmerly.
Where alerts arrive
As each company states it
WarmerlyMailreach
- At most one email per user a day
- Health webhooks on Agency
- No Slack alert found
Slack and webhooks
- Slack or webhook on score changes
- Alerts on automatic spam tests
- Which plans include them is not stated
Read on mailreach.co on 21 October 2026.
How Warmerly does it
Warmerly, in detail.
Email first, with a fingerprint rule that keeps a repeat quiet, plus signed health webhooks on Agency.
01
An email digest
Alerts are grouped and sent as at most one email per user per 24 hours. An unchanged unfixed problem waits 14 days before it can raise another, and a changed or worsened one waits 24 hours.
Warmerly product, checked 21 October 2026
02
What raises one
A health score that falls 15 points or more or sits below 50, a mailbox that disconnects, DNS changes, and a domain or IP blocklisting.
Warmerly product, checked 21 October 2026
03
The engine runs every 15 minutes
The alerts job evaluates mailboxes every 15 minutes, then the digest goes out at most once a day.
Warmerly product, checked 21 October 2026
04
Health webhooks on Agency
Signed webhooks send mailbox health events such as score drops, authentication failures and DNS changes. They need the Agency plan.
Warmerly product, checked 21 October 2026
05
No Slack alert found
We found no Slack alert in the alerts code.
Warmerly product, checked 21 October 2026
06
Eight alert kinds
Score drop, score floor, disconnected, authentication failure, DNS change, domain blocklisting, IP blocklisting and delivery that cannot be observed. Some need action by the customer and some do not.
Warmerly product, checked 21 October 2026
07
Repeats follow the news, not the clock
Each alert records what it was about, such as the failing DNS codes or the blocklist zones. The same fault waits 14 days, a new or worse one waits 24 hours, and a reminder is worded as still, so it does not read as a duplicate.
Warmerly product, checked 21 October 2026
08
New mailboxes are given a grace period
Score drop and score floor alerts are held for the first 14 days of warmup or until 3 health snapshots exist, because one spam message moves an early score by tens of points. Disconnects, missing records and blocklistings still alert on day one.
Warmerly product, checked 21 October 2026
09
Fixed faults are withdrawn
When the sweep that raised an alert measures the fault clear, the alert is resolved, so a problem fixed before the daily digest is never mailed. Only a new measurement resolves one, never the passing of time.
Warmerly product, checked 21 October 2026
10
Webhook delivery rules
Sixteen event types, signed with HMAC SHA256 in X-Warmerly-Signature. A sweep every 5 minutes sends them, each tried 3 times with a 5 second timeout, and a subscription switches itself off after 10 sweeps with failures. It is not real time.
Warmerly product, checked 21 October 2026
11
Paused mailboxes still alert
A mailbox paused for poor health still raises a score alert, because that alert is the only notice the owner gets that it was paused.
Warmerly product, checked 21 October 2026
How Mailreach does it
Mailreach, in detail.
Slack and webhook alerts on reputation changes and on scheduled tests, with an overview page for larger accounts.
01
Slack or webhooks on score changes
Its warm-up page says you can get Slack or webhook notifications when reputation scores change.
mailreach.co/email-warmup · read 21 October 2026
02
Alerts on automatic tests
Automatic spam tests come with instant alerts of deliverability errors by Slack or webhook.
mailreach.co/email-spam-test · read 21 October 2026
03
Webhooks in the API docs
Its API docs say you can be notified in real time when something changes on an account or test.
docs.mailreach.co · read 21 October 2026
04
Agency reporting window
Its agency page says reputation tracking covers the last 48 hours.
mailreach.co/agency · read 21 October 2026
05
Per address score and per provider health
It says it tracks a reputation score per address and lets you check account health per provider.
mailreach.co/email-warmup · read 22 October 2026
06
An overview page from six accounts
With 6 or more accounts it offers average reputation per domain, per tag and per provider on an overview page.
mailreach.co/email-warmup · read 22 October 2026
07
Alerts as step four of warmup
The five step description puts monitoring with real time insights and Slack alerts as step four.
mailreach.co/how-email-warmup-works · read 22 October 2026
08
Assistants and webhooks in the API
The API docs list real time webhook notifications and MCP access for AI assistants such as Claude and ChatGPT, next to the core spam test and inbox endpoints.
docs.mailreach.co · read 22 October 2026
What Mailreach does not say
We looked, and found no statement on these. That is about its published pages only, not about the product.
- Which plans include the alerts
- How soon after a change an alert is sent
- A list of alert types
- Whether a repeat of an unchanged problem is suppressed
- The webhook event types and payload
- Whether alerts are included on every plan
- Whether alerts can be sent by email
Where the sources disagree
We report each version rather than pick one.
- Its pages say alerts are instant or real time, and none says how soon after a change they arrive.
The numbers
Only what we could verify.
| Measure | Warmerly | Mailreach |
|---|---|---|
| Alerts | An email digest, at most one a day; health webhooks on the Agency plan; no Slack alert found. | Slack or webhook alerts when reputation scores change and on automatic spam tests. |
| Alert channels | Email, plus webhooks on Agency | Slack and webhooks |
| Alert frequency | At most one email a day | Not stated |
| Checks run | Every 15 minutes | Not stated |
| Alert kinds | 8 | Not stated |
| Webhook events | 16 event types, Agency | Not stated |
| Webhook delivery | Sweep every 5 minutes, 3 tries | Described as real time |
| Repeat of an unchanged fault | After 14 days | Not stated |
| Score alerts on a new mailbox | Held for 14 days | Not stated |
In practice
What it means for you.
Our reading of the facts above. Not a promise, and not the only reasonable reading.
If your team lives in Slack, Mailreach fits
Warmerly's alerts reach you by email, and webhooks need Agency.
A daily digest is quieter
Warmerly caps alert email at one a day on purpose, after customers asked for fewer repeats.
A worst case for the inbox
A workspace with 7 mailboxes whose DNS has not changed gets at most one digest a day. Without the fingerprint rule, as the doc records, a flat 24 hour cooldown once mailed the same warning every morning for weeks. With it, the same fault produces a reminder after 14 days.
Speed against quiet
Warmerly's engine evaluates every 15 minutes but mails at most daily, and webhook sweeps run every 5 minutes. If you need a Slack message within moments of a drop, Mailreach's stated real time Slack alerts are a closer fit, though its pages give no delay in minutes.
Scale your alert routing
Mailreach's overview page starts at 6 accounts and groups by domain, tag and provider. Warmerly's webhooks need Agency, which is $179 a month for 100 mailboxes, so a team that wants machine readable alerts should price that in.
Pushing Warmerly alerts into Slack
A webhook on Agency can post to any URL you control, so a small relay can forward score drops to a Slack channel. That is your own glue, not a Warmerly Slack alert.
Who it suits
Pick the one that fits.
Warmerly
Warmerly is the better fit if
- You want few, grouped alert emails
- You want health webhooks on a larger plan
- You do not need Slack
- You want repeat alerts kept quiet by design
- You want new mailboxes left alone while warmup settles
- You want signed webhooks with documented retry rules
Mailreach
Mailreach is the better fit if
- You want alerts in Slack
- You want webhooks without a top plan
- You want alerts on scheduled spam tests
- You want Slack in the alert path without building a relay
- You want an overview grouped by domain, tag and provider
- You want alerts tied to scheduled spam tests
Questions
Does Mailreach send Slack alerts?
Yes. Its pages say it can notify you by Slack or webhook when reputation scores change and when automatic tests find errors (read 21 October 2026).
Does Warmerly send Slack alerts?
We found none. Alerts arrive as an email digest, at most one per user a day, and signed health webhooks are on the Agency plan.
How often will Warmerly repeat an alert?
A new or worse fault can alert again after 24 hours. The same unfixed fault waits 14 days and its title says still.
Are Warmerly's webhooks real time?
No. A sweep runs every 5 minutes and sends events in order, with 3 attempts each. They need the Agency plan.
Does Warmerly alert me about a brand new mailbox's score?
Not in the first 14 days of warmup. Disconnects, missing DNS records and blocklistings still alert on day one.
Sources
- Mailreach email warmup
- Mailreach email spam test
- Mailreach API documentation
- Mailreach API documentation
Mailreach pages were read on 21 October 2026. Plans and wording change, so check the vendor's own page before you decide. Warmerly details come from the product as it runs today.
More features
- All features
- Starting price (per month)
- Pricing model
- Cost at 5, 25 and 100 mailboxes
- Free plan or trial
- Warmup network size
- Daily warmup volume
- Spam rescue
- Spam test and inbox placement
- SPF, DKIM, DMARC and blocklist checks
- Campaign sending
- Mailbox providers
- API access
- Agencies and client mailboxes
- Data hosting and security
See it on your own mailbox.
Connect a mailbox. Warmerly runs alongside whatever you send from now, so you can compare before you move anything.
Free plan, no card. Paid plans: 7-day trial, first charge on day 8.