Inconsistent email volume spikes
Overview
Mailbox providers are sensitive to sudden spikes in email volume, especially if they deviate from a sender's usual behavior. If you send more than double your highest daily volume in the past 30 days, it may be flagged as unusual activity.
EX: If your highest volume in the last 30 days is 5,000, sending over 10,000 in a single day could raise red flags.
Large spikes may lead to delivery delays or blocks by mailbox providers.
Learn more about common deliverability issues and how to resolve them.
Steps to take when sending a large volume of emails
To avoid deliverability issues when sending an unusually large volume of emails, it's essential to follow a gradual ramp-up strategy. This aligns sending behaviors with mailbox providers' expectations and reduces risk of messages being filtered or blocked. Follow these steps:
- Identify the recent (<30 days) maximum volume.
- Identify the total volume for this send.
- Create a ramp-up plan that begins at the recent maximum daily volume and doubles that amount each day until the total volume is reached.
EX: A sender typically sends 5,000 emails and wants to send 35,000 emails at once. The volume should be broken down as follows:
Day | Email volume |
1 | 5,000 emails |
2 | 10,000 emails |
3 | 20,000 email |
Following this strategy senders can minimize unexpected deliverability issues as it is inline with expectations of mailbox providers, provided other principles of deliverability best practices are continued.