IP warm-up schedule for a new mail server
A new sending IP has no reputation, so mailbox providers watch it closely. A conservative warm-up starts at about 50 emails a day and roughly doubles every two to three days while bounces and complaints stay low, reaching normal volume in two to four weeks. Slow down at the first warning signs.
Why warm-up matters
Gmail, Outlook and Yahoo judge a new IP and domain on how it behaves in its first weeks. A sudden jump from zero to thousands of messages looks like abuse, even when the list is clean, and is the fastest route to blocks and spam-folder placement. Warm-up builds a record of steady volume, low bounces and engaged recipients.
A conservative schedule (a starting point, not a guarantee)
| Days | Emails per day (all domains) | Who to send to |
|---|---|---|
| 1 to 3 | 50 | Your most engaged recipients, plus seed accounts you control |
| 4 to 6 | 100 | Recipients who opened or clicked recently |
| 7 to 9 | 250 | Engaged recipients |
| 10 to 12 | 500 | Engaged recipients |
| 13 to 15 | 1,000 | Add recipients who engaged in the last 90 days |
| 16 to 18 | 2,500 | Widen gradually |
| 19 to 21 | 5,000 | Widen gradually |
| 22 onward | Raise by 25 to 50% a day | Only while bounces and complaints stay low |
Adjust to your own results. If a day goes badly, repeat the previous volume instead of moving up.
Signals to watch, and what to do
- Hard bounces above about 2%: stop and clean the list before you continue.
- Spam complaints: major providers publish a ceiling of 0.3% and recommend staying well under 0.1%; pause growth if you approach it.
- Deferrals or 4xx responses from one provider: lower that provider's rate limit and let the queue drain; do not retry harder.
- Blocklist listing: stop sending from that IP, find the cause and follow the list's delisting process.
Rules that make warm-up work
- Authenticate first: SPF, DKIM, DMARC and matching reverse DNS before the first message.
- Send consistently every day rather than in rare large bursts.
- Send content people asked for; low engagement hurts reputation faster than volume does.
- Warm up each new IP and each new sending domain; reputation does not transfer between them.
- Spread volume across several IPs only after each one is warm.
How TurboMTA helps
TurboMTA lets you set per-domain rate limits and backoff on bounces, so you can hold Gmail to a slower pace than a smaller provider, and a dashboard shows the queue and delivery state. Combined with VirtualMTA IP pools you can add IPs one at a time as they warm.
Keep reading
- Turn a VPS into an email server: DNS records and setup before you warm up.
- Gmail and Yahoo bulk sender rules: The thresholds behind the numbers above.
- What unlimited sending really means: The limits that matter.
Frequently asked questions
How long does IP warm-up take?
Plan on two to four weeks for a new IP. A conservative start is about 50 emails a day, roughly doubling every two to three days while bounces and complaints stay low, to the volume you need. Skipping warm-up is the most common reason a new sending IP gets blocked.
What do Gmail and Yahoo require from bulk senders?
Since 2024 senders of large volumes to Gmail and Yahoo addresses need SPF and DKIM, a DMARC policy, matching reverse DNS, TLS, one-click unsubscribe on marketing mail and a low spam-complaint rate (under 0.3%, ideally under 0.1%). Microsoft has enforced similar rules for Outlook.com, Hotmail.com and Live.com since May 2025. Check each provider's current guidelines.