Our job here at SocketLabs is to give the messages you are sending the highest odds of reaching the recipient's inbox. In order to maximize the rate at which this happens we will initially throttle the rate we send your messages. We refer to the period of time when we throttle your delivery rate as the "warm up" period.
This rate limiting occurs inside the SocketLabs network and does not affect the rate at which we will accept your messages at our SMTP gateway, or via our Injection API. The limits that we apply are based on the destination of your messages. If you are sending a significant volume of mail to a single specific domain, you may be more likely to encounter our restrictions. A normal flow of mail that is dispersed to an array of different domains is less likely to encounter limitations.
In this day and age anti-spam systems and email filtering tools are very smart. Gmail’s filters, for example, look at hundreds of different data points when determining inbox placement of a message. Our goal with restricting delivery rates is to introduce your messages to the filters in a way that lets the filter know the messages are legitimate.
To understand why this is necessary you have to think about it from the point of view of a mailbox provider. Recent estimates have claimed that over 80% of email traffic on the internet is spam. The spammers are in a constant battle with mailbox providers in an effort to get their messages into the inbox. Once a spammer's attack avenue becomes blocked, they quickly scatter to find a new route for delivery. This means that mailbox providers are under a constant onslaught of attacks that originate from all new sources. Since spam sources are easily detected and blocked, often times malicious users will send as much mail as they can as quickly as possible.
The way that we initially restrict delivery rates helps make you appear as a legitimate sender and makes your messages more likely to land right into the inbox.
The initial delivery restrictions we put in place vary greatly depending on a multitude of aspects including the type of mail processing, and plan volume. Delivery rates start as low as 50 messages per hour per domain. SocketLabs customers on service plans that include under 25,000 messages per month are unlikely to ever even encounter a delay in message processing.
Larger volume senders of marketing messages are the most likely to encounter delivery delays during the warm up period.
There is no one single formula to how long a warm up period will last. Low volume transactional senders may see warm up periods end within a single day, where marketers may have their delivery rates throttled for a month or more. Our platform will automatically increase delivery rates as mailbox providers get used to seeing your messages. The rate at which this occurs is based on many factors. The two biggest influencing factors are quality and quantity. We represent the quality of your mail via the Quality Score. The higher the quality score the faster your warm-up period will conclude.
Our team of email delivery experts are constantly monitoring mail queues across all servers and will often take action to prevent any issues from arising from due to throttling limits. If there is a specific reason you need messages to process more quickly do not hesitate to contact our support department. The fastest way to get help is by emailing firstname.lastname@example.org.
Tips Specifically For Marketers
Marketers should focus on a few things during their warm-up period.
- Contact your most loyal and most active customers first
- Be sure that the recipients of your messages are expecting them
- Don’t start sending from a new domain at the same as starting with our service