What are the consequences of not warming up an IP address correctly?

Marketer from Email Geeks shares an example of a client who warmed up too fast (1k-2k one day then 100k the next day) and were marked as spam at Yahoo for months.

Email marketer from StackExchange explains that ISPs use algorithms to detect spammers. A sudden spike in traffic from a new IP looks suspicious, so ISPs will filter the mail as spam until the server builds up a good reputation.

Email marketer from Mailjet Blog explains that not warming up your IP correctly will seriously affect your deliverability. Email providers will consider you a spammer as they can't verify the legitimacy of your sending practices. It will lower your sender reputation and your emails will bounce or end up in the spam folder.

Email marketer from HubSpot Blog responds that failing to warm up an IP address can lead to poor deliverability, meaning your emails may end up in the spam folder or be blocked altogether. This can damage your sender reputation and impact your email marketing performance.

Email marketer from EmailGeeks Community responds that failing to warm up an IP address leads to immediate deliverability problems. This person has seen ISPs automatically block emails until the IP gains a positive reputation through a gradual warm-up.

Email marketer from SendGrid Blog shares that without proper IP warming, your emails are more likely to be marked as spam. ISPs will be suspicious of sudden large volumes of emails from a new IP address, hurting sender reputation and deliverability.

Marketer from Email Geeks explains that to prove the impact of a poor IP warm up, send a full base email to a brand new IP address, collect the stats and present it to the customer, split up across ISPs. Suggesting it won't burn the IP by doing it for a week or two.

Email marketer from Reddit answers that sending too much email from a new IP all at once will damage your sender reputation. Major email providers immediately distrust the IP and often send all messages to spam folders.

Expert from Word to the Wise shares that sending too much volume without warming an IP can result in inbox providers treating your mail with suspicion. This can lead to placement in the spam folder, or even complete blocking of your messages.

Expert from Spam Resource explains that if you don't warm up your IP address, you run the risk of being tagged as a spammer. ISPs see a new IP sending a huge volume of email as a red flag, leading to deliverability issues and potential blacklisting.

Documentation from RFC Editor explains that sending a high volume of unsolicited email from a new IP address can cause it to be listed on various blocklists, due to perceived spam activity. This makes the email server untrusted.

Documentation from Microsoft Docs shares that inadequate IP warming can lead to deliverability issues with Outlook.com. Microsoft's filtering systems may flag your emails as spam if you send a large volume of emails from a new IP address without gradually increasing volume and establishing a positive sending reputation.

Documentation from Google Postmaster Tools explains that a sudden spike in email volume from a new IP address, without a proper warm-up, can negatively impact your IP reputation with Gmail. This can result in emails being filtered to spam or blocked.

Documentation from SparkPost explains that not warming up your IP address correctly can damage your sender reputation and deliverability. Email providers will consider you a spammer as they can't verify the legitimacy of your sending practices. It will lower your sender reputation and your emails will bounce or end up in the spam folder.