A) Though the below are hourly limits, it does not mean that the numbers below are your maximum "list member" size. In other words, if your hourly mail limit is 100 emails, you can still send your emails to lists larger than 100 members, but your script settings may need to be adjusted to be in compliance to not exceed these hourly limits.
B) Though the below are hourly limits, it does not mean that you can expect to send email 24 hours per day at these limits. In other words, if your hourly email limit is 100 messages per hour, sending 2400 emails per day is not within acceptable use. If you have a Dedicated Plan or Cloud Server (Enterprise Cloud or Cloud VDS), you can set your own mailing schedules as desired without any outbound limits.
Current Shared Plans:
Old Shared Hosting Package Limits:
Budget Shared Hosting Plans - 100 emails per hour
Advanced Shared Hosting Plans - 250 emails per hour
Professional Shared Hosting Plans - 500 emails per hour
Mailing lists available from your control panel:
Mailman - All Features
PHP List - All Features
What does this mean?
If you have a mailman mailing list:
That has more than 5000, 500, 250 or 100 list members respectively, anything after your hourly email limit will most likely not be delivered. The server will automatically toss it in the garbage. This is because mailman does not throttle outbound email efficiently. Several factors can allow you to exceed 100, 250, and the 500, 5000 list member limit, like time of day, time at which the mailman list was sent, server load and other factors. However for easy numbers plan on list sizes no greater than your hourly email limit when using mailman.
If you have a php list mailing list:
You can have more than 5000, 500, 250 or 100 list members respectively. You can bypass the problem with trying to deliver more than 500, 250 or 100 emails to your list members by throttling the rate at which emails are sent. To see how this works, please see this thread:
Email rate throttle in php list
If you have a vBulletin forum script:
You can have more than 5000, 500, 250 or 100 forum members respectively. You can bypass the problem with trying to deliver more than 5000, 500, 250 or 100 emails to your forum members by throttling the rate at which emails are sent. To see how this works, please see this vBulletin Plugin:
Email rate throttle in vBulletin
It should be noted and often is not, that when you see email "limits" (if your host even advertises them) that your regular sending patterns, like replying to your buddy George about tonight's dinner reservation counts as one email. That means that now you only have 499 list members who will actually get your list's email, assuming you are on a package that supports 500 emails per hour.
You should take into account your regular email work flow and list size when selecting a hosting plan. If you anticipate that you send out something like one email per minute (wow, you can type fast!) that would be 60 emails that you replied to (sent) in one hour. Then, if you decided to send of your mailing list within that same hour, you could successfully send to a list size of 440 members on a Professional Shared Web Hosting plan, which comes with 500 emails per hour.
- Accounts that are reported by other ISP's or feedback loops, honeypot email addresses, or RBLs for obvious spam complaints may be removed from our servers depending on the situation. Accounts that are discovered which are being reported too frequently for spam, generally means that the list owner did not, but should be using a Double Opt-in email list with clear unsubscribe instructions. Double Opt-in means that your list members should have signed up, by themselves, specifically to your mailing list and not added by you under any other circumstances. When they opt-in, a confirmation email is sent to the address that they left on your mailing list subscription form. When they click the confirmation, they have now opted in to receive your email, two times. Once to submit their email address, and twice when they click the confirmation link. While we do not require your list to be double opt-in, it is generally a good idea.
- If you purchased a list of email addresses, sending unsolicited email to this type of list is strictly forbidden.
- SMTP AUTH RELAY is limited to 100 emails per hour on all packages by default. You can modify or completely eliminate this limitation when you have a dedicated or cloud server. On shared servers and semi-dedicated servers, AUTH RELAY is is set to 100 to prevent server blacklistings resulting from users who share the server with you, who's PCs have been infected by a virus or other malware which tries to login to the email server to send spam from their account.
- Programs like SendBlaster or similar email programs that run from your PC which use SMTP AUTH RELAY will not be able to send more than 100 emails per hour on shared or semi-dedicated servers. For this type of email, you would require a Dedicated Server or Cloud Server.
Why does GlowHost rate-throttle outbound email?
The reason for the throttles is to provide the most reliable email hosting experience for ALL customers that share the mail server. It helps us to prevent mailserver blacklistings when a spammer makes his way onto a shared server.
We never know who is going to sign up for a hosting account and attempt to send spam from a server. We never will know when a long time and trusted customer is going to decide that one day they are going to test out their "marketing skills" and initiate a mailing campaign to a 50,000 email address list that they bought on ebay for $9.95.
Email throttles help everyone to negate the blacklistings that many long-time web site operators are familiar with, especially those coming from bargain basement hosts that have no limit email hosting where server performance suffers drastically our outbound email is unreliable or bouncing back due to blacklistings. Though our system is not 100% effective in preventing blacklistings, we do minimize them drastically for our users using these methods.
All web hosts including major players like yahoo end up on these spam blacklists.
Blacklistings occur when a certain quantity of email has been reported to third party RBLs (Remote Block List) like Spamcop. These RBLs will add reported mailservers to it's internal block lists.
Subscribers to these RBLs include major ISP like AOL, Comcast and even smaller ISP like GlowHost subscribe to RBLs. When these Internet Service Providers receive mail from a mailserver that is on one of their (subscribed) RBLs, it is immediately returned to sender, rendering the email undeliverable.
Basically, an ISP subscribing to an RBL means penalize every web site that uses a particular mailserver host, because one unscrupulous spammer, and sometimes even an unknowing newbie, ruins it for the whole bunch. Ever heard of "sour grapes?"
Blacklistings can last 24 hours and even longer for repeat offenders. Generally web hosts have little or no control over being removed from these RBLs with the exception of a few RBL providers that allow automatic "de-listing."
However if a host removes themselves, and the spam complaints continue to roll in, the black listing is re-initiated, this time with a longer wait for de-listing, and that can go on indefinitely based on how bad the problem is with a particular mail server.