Sending campaign emails through Recruiterflow means your emails go out from your own connected inbox — Gmail or Outlook. That makes sender reputation entirely your own. Send too much too fast and you risk spam filters, IP blacklisting, and your domain landing on blocklists.
Use the limits below as a guide. They're not Recruiterflow platform caps — they're deliverability best practices based on what email providers tolerate.
Emails per day
Safe: Up to 60
Moderate: 61–100
Risky: 101–150
High: 151–200
Very High: 201–350
Abandon Ship: 350+
Up to 60 per day keeps you well within what Gmail and Outlook treat as normal human behaviour. Above 100, spam filters start paying attention — especially if open and reply rates are low. Above 350, you're likely to see deliverability damage regardless of content quality.
Pro tip: If you need to send more than the recommended daily limit, use email aliases to distribute volume across multiple sender addresses. See Using Shared Aliases in Recruiterflow.
Emails per hour
Safe: Up to 10
Moderate: 11–15
Risky: 16–20
High: 21–25
Very High: 26–35
Abandon Ship: 35+
Burst sending — firing off 50 emails in 20 minutes — is one of the fastest ways to get flagged. Even if your daily total is fine, a concentrated burst looks like automated spam to most email servers.
Delay between emails
Safe: 90+ seconds
Moderate: 75–90 seconds
Risky: 61–75 seconds
High: 51–60 seconds
Very High: 41–50 seconds
Abandon Ship: Under 40 seconds
Spacing emails out makes send patterns look organic. Under 40 seconds between sends is a strong spam signal — most email providers will catch it.
What exceeding these limits leads to
Spam filtering: Gmail, Outlook, and others flag high-volume, low-delay activity. Your emails skip the inbox and go straight to spam.
IP blacklisting: Sustained high-volume sending can get your sending IP blacklisted. Once that happens, emails from your domain are blocked entirely until the listing is reversed.
Domain reputation damage: Your domain's sending reputation is cumulative. Burning it takes days; rebuilding it can take months.
Other ways to protect deliverability
Personalise messages: Generic mass emails get lower engagement, which signals to email providers that recipients don't want them. Use merge fields so every email feels relevant.
Clean your lists: Sending to invalid or inactive addresses increases bounce rates, which hurts your domain. Remove them before launching a campaign.
Avoid spam trigger words: Phrases like "Free," "Limited time offer," and "Make money fast" reliably trigger filters. Keep subject lines and body copy professional.
Use multiple senders: Adding multiple senders to a campaign distributes volume in round-robin fashion, reducing the load on any single inbox. Recruiterflow's smart sender assignment can also automatically route replies to the sender already in conversation with that recipient. See How Does Recruiterflow's Smart Campaign Sender Assignment Work?