Email Rate Limiting: Why Throttling Protects Deliverability
Sending too fast looks like an attack to mailbox providers. Here is how throttling and rate limits keep your mail flowing.
Blast 100,000 emails in one minute and mailbox providers treat it like an attack — they throttle, defer or block you. Rate limiting paces delivery so you stay welcome.
Why providers limit you
Each provider enforces its own per-connection and per-hour limits. Exceed them and you get 421 deferrals. A good platform respects these automatically and retries politely.
Throttling on your side
- Spreads a large send over time instead of one spike.
- Honors provider-specific limits per receiving domain.
- Backs off when it sees deferrals, then resumes.
Send email that actually lands in the inbox
API and visual editor, SPF/DKIM/DMARC out of the box, analytics and warm IPs. Free tier — 200 emails/month, no card required.
It is also reputation protection
A smooth, steady sending pattern reads as a legitimate sender. A jagged spike reads as a compromised account or spammer. Pacing literally improves how providers score you.
Let the platform handle it
Sendersy queues and throttles automatically per receiving domain, so you press send once and it delivers smoothly. Start free.
Owns SMTP relays, queues and monitoring. Knows why a message is stuck before you ask.
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