Your email list is the foundation of your email marketing programme. How well you manage and segment your list directly determines your deliverability, engagement rates, and sender reputation. This article covers list building best practices, how to structure your contacts, segmentation strategies, and how to keep your list healthy over time.
What Is List Segmentation?
Segmentation is the practice of dividing your email list into smaller, targeted groups based on shared characteristics — so you can send each group content that is specifically relevant to them rather than blasting the same message to everyone. Segmented campaigns consistently achieve higher open rates, higher click rates, and lower unsubscribe rates than non-segmented sends.
Common Segmentation Dimensions
| Dimension | Segment Examples | Use Case |
|---|---|---|
| Engagement level | Active (opened in last 30 days), Lapsed (31–90 days), Inactive (>90 days) | Send re-engagement campaign to Inactive before removing them; send exclusive offers to Active |
| Purchase history | First-time buyers, repeat customers, high-value customers, never purchased | Send loyalty rewards to repeat buyers; send first-purchase incentive to never-purchased |
| Product interest | Clicked product category A, browsed category B, abandoned cart with product C | Send product-specific promotions based on demonstrated interest |
| Geography | City, state, region, country | Send city-specific event invitations; localise currency and offers |
| Subscription date | New subscribers (last 7 days), recent (last 30 days), long-term (>6 months) | Trigger welcome series for new; send anniversary offer to long-term |
| Plan / account type | Trial users, paying users, enterprise accounts | Send upgrade prompts to trial; feature announcements to paying; dedicated content to enterprise |
How to Implement Segmentation with MigoSMTP
MigoSMTP does not store your contact lists — it is a delivery infrastructure platform. Segmentation logic lives in your application, CRM, or marketing automation tool. MigoSMTP receives the final, already-segmented recipient list for each send via the API.
Here is the recommended workflow:
- Store contacts in your system — your own database, CRM (HubSpot, Salesforce), or spreadsheet.
- Apply segmentation logic — write a query or use CRM filters to produce a segmented list.
- Export or fetch the segment — get a list of email addresses (with any personalisation variables) for that segment.
- Send via MigoSMTP bulk API — pass the recipient list with per-recipient variables to the send endpoint.
- Tag the send — use campaign tags to label the send by segment for filtered reporting.
List Hygiene — Keeping Your List Healthy
List hygiene is the ongoing practice of keeping your contact list clean, engaged, and free of addresses that damage your deliverability. Poor list hygiene is the single most common cause of declining email performance.
Hygiene Tasks and Frequency
| Task | Frequency | How to Do It in MigoSMTP |
|---|---|---|
| Remove hard bounces | After every campaign | Export bounced addresses from Delivery Reports; remove from your sending list; MigoSMTP auto-suppresses them |
| Honour unsubscribes | Real-time — immediately on each unsubscribe event | MigoSMTP auto-adds unsubscribers to suppression list via webhook event email.unsubscribed |
| Remove inactive subscribers | Quarterly | Identify recipients with zero opens in 90 days from your delivery logs; run a re-engagement campaign; remove non-responders |
| Address validation | At point of collection | Validate format at sign-up with regex; use double opt-in to confirm address validity |
| Deduplicate contacts | Monthly | Run deduplication on your contact database to remove duplicate email addresses |
Re-Engagement Campaign — Before You Remove Inactive Subscribers
Before removing inactive subscribers from your list, run a re-engagement campaign to give them one last chance to opt back in. This is both good practice and an opportunity to recover dormant value:
- Identify subscribers with no email opens in the last 90 days.
- Send a single email with a compelling subject line and a one-click re-opt-in button (e.g. "Are you still interested? Click here to stay subscribed").
- Wait 7 days.
- Anyone who did not click to re-opt-in should be removed from your active sending list and added to your suppression list.
Importing Your Existing Contact List
If you have an existing contact list you want to migrate to MigoSMTP sends:
- Export your list from your current provider or CRM as a CSV file.
- Ensure the CSV has at minimum: an
emailcolumn and afirst_namecolumn. - Validate the list — remove duplicates, invalid formats, and known bounces.
- Import suppressed addresses from your previous provider into MigoSMTP's suppression list to avoid re-sending to people who already unsubscribed.
- Warm up your sending gradually with this migrated list — do not blast the full list on day one.