Your site goes down at 3 AM. You find out at 9 AM when a customer emails. By then you've lost hours of uptime — and trust.
Getting notified the moment your website goes down changes that. You can fix or escalate before most people notice. This guide walks you through how to set up downtime notifications using email, SMS, Slack, and other channels so you're always the first to know.
Why "Website Down" Notifications Matter
You can't fix what you don't know about
If no one is watching your site 24/7, downtime often goes unnoticed until a user complains. By then:
- Revenue may be lost (e-commerce, signups, ads).
- Trust is damaged ("Why didn't they know?").
- Debugging is harder (you don't know exactly when it started).
An alert the moment the site fails gives you a clear start time and a chance to respond before it becomes a crisis.
Not all "down" is obvious
Your site might be:
- Fully down — Server unreachable, 500 errors.
- Slow — Taking 10+ seconds, so users give up.
- Broken for some — Down in one region or for certain devices.
Monitoring that checks from multiple locations and tracks response time can alert you to all of these, not just total outages.
Alerts need to reach you where you are
An email that lands in a crowded inbox might be missed. An SMS or Slack message is more likely to get attention. The right channel (email, SMS, Slack, etc.) matters as much as having monitoring in the first place.
How Downtime Notifications Work
1. Something checks your site on a schedule
A monitoring service (or your own script) hits your URL every 1–5 minutes from one or more locations. It checks that the site responds with a successful status (e.g. HTTP 200) and optionally that response time is under a threshold.
2. When a check fails, an alert is sent
If the site doesn't respond, returns an error (4xx/5xx), or is too slow, the monitor is marked "down" and a downtime alert is sent to the channels you configured: email, SMS, Slack, Discord, webhook, etc.
3. When the site recovers, you can get a recovery alert
Many tools also send a recovery or "back up" notification so you know when the incident ended and can stop investigating (and optionally post an update to users).
The whole loop: check → fail → alert → fix → recover → (optional) recovery alert.
Which Notification Channels to Use
- Pros: Universal, no extra setup, good for records.
- Cons: Easy to miss if inbox is busy; can be delayed or filtered.
Best for: Non-critical sites, backup channel, or teams that live in email.
SMS
- Pros: Hard to miss; works when you're away from the computer.
- Cons: Often limited or paid per message; can wake you at night.
Best for: Critical sites and on-call people who need to be woken up.
Slack (or Discord, Teams)
- Pros: Fits where many teams already work; can use a dedicated #alerts channel; supports rich messages and links.
- Cons: Only works if someone is in the app; need to avoid muting the channel.
Best for: Teams that use Slack daily; great for fast reaction during work hours.
Webhooks
- Pros: Flexible; can trigger PagerDuty, Opsgenie, custom dashboards, or internal tools.
- Cons: Requires something to receive and act on the webhook.
Best for: Integrating with existing incident or on-call systems.
Push (mobile app)
- Pros: Direct to your phone; good for on-the-go.
- Cons: Depends on the monitoring tool offering an app and you having it installed.
Best for: Solo operators or small teams who want phone alerts without SMS cost.
Step-by-Step: Set Up Website Down Notifications
Step 1: Choose a monitoring tool
Pick a service that:
- Checks your URL(s) on a schedule (e.g. every 1–5 minutes).
- Sends alerts when the site is down (and optionally when it recovers).
- Supports at least one channel you'll actually notice (email, Slack, SMS).
Many tools offer a free tier so you can try before paying.
Step 2: Add your website URL(s)
Add the URL(s) you care about most: usually your homepage and maybe a critical page (login, API health, checkout). Each URL is typically one "monitor." Start with 1–3; add more as needed.
Step 3: Set the check interval
Choose how often the tool checks (e.g. 1, 5, or 10 minutes). Faster checks mean faster alerts but may cost more or hit limits on free plans. For most sites, 5-minute checks are a good balance; for business-critical, 1-minute is better.
Step 4: Configure notification channels
Add the channels where you want downtime (and recovery) alerts:
- Email — Add the address(es) that should get alerts.
- Slack — Connect the app, pick a channel (e.g. #alerts), save.
- SMS — Add phone number(s) if the plan supports it; be aware of limits or cost.
- Webhook — Paste the URL of your incident system or script.
Send a test notification to confirm delivery.
Step 5: Optional: Set response time alerts
If the tool supports it, set a threshold (e.g. "alert if response time > 5 seconds"). That way you're notified when the site is slow or degrading, not only when it's completely down.
Step 6: Optional: Add SSL expiry alerts
If your tool checks SSL, enable expiry alerts (e.g. 30, 14, 7, 1 day before). That prevents "site down" caused by an expired certificate.
Best Practices for Downtime Alerts
Alert where you'll see it
Use at least one channel you check often. For many teams, that's Slack or SMS for critical monitors and email as a backup or for less critical ones.
Use a dedicated channel or group
Create a channel like #alerts or #downtime so alerts don't get lost in general chat. Only add people who should act on them.
Include recovery notifications
Turn on "recovery" or "back up" alerts so you know when the incident is over and have a clear duration for post-incident notes.
Avoid alert fatigue
- Don't alert on every single failed check if the tool retries (e.g. "alert after 2 consecutive failures" or "after 2 minutes down").
- Use different channels or severity for critical vs non-critical sites.
Document what to do when an alert fires
Keep a short runbook: who checks first, how to verify the site is down, who to contact (hosting, DNS, etc.), and where to post updates (e.g. status page). Update it when your setup changes.
How Webalert Sends Downtime Notifications
Webalert is built to get you notified the moment something fails:
- Multiple channels — Email, SMS, Slack, Discord, webhooks. Use one or several per monitor.
- Down and recovery — Alerts when the site goes down and when it comes back up.
- Fast checks — 1-minute checks on paid plans so you know within a minute.
- Response time — Optional alerts when the site is slow, not just down.
- SSL — Certificate monitoring and expiry alerts so you're not surprised by an expired cert.
- Test notification — Verify each channel before you rely on it.
See features for notification options and pricing for plans.
Quick Checklist: Get Notified When Your Site Goes Down
- Monitoring tool checks your URL at least every 5 minutes (1 minute for critical).
- At least one alert channel is configured (email, Slack, or SMS).
- Test notification sent and received.
- Recovery alerts enabled so you know when the site is back up.
- Optional: response time threshold and SSL expiry alerts.
- Runbook or process documented for when an alert fires.
Final Thoughts
Getting notified when your website goes down is one of the highest-impact steps you can take for reliability. Pick a tool that checks often enough, alerts you on a channel you'll see, and optionally tracks response time and SSL. Then test the alerts, document the response process, and you're set. You'll stop finding out about outages from users and start fixing them in minutes.