The Scenario
You are a CRM manager. You suspect your Omnisend contact list has thousands of duplicates accumulated over four years, three import tools, two agencies, and at least one emergency CSV paste.
You need the full list in an Excel workbook so you can find the duplicates, mark the ones to remove, and re-import a clean version. The campaign next month segments by subscription status, and duplicates mean subscribers get emails twice.
The bad version of this week:
- You look for a contact export in Omnisend
- Find one, but it caps at 5,000 rows and you have 47,000 contacts
- Export in 10 chunks, get 10 separate CSV files
- Paste them into Excel, fix the duplicate headers at rows 5001 and 10001
- Start looking for duplicate emails across 47,000 rows
- Three days later you have cleaned 8,000 rows and still have 39,000 to go.
The fast version is one prompt and the flagged duplicates are in the workbook before your next meeting.
The Easy Way: One Prompt in SheetXAI
SheetXAI pulls the full Omnisend contact list into the workbook and flags duplicates, handling the API pagination so you never have to stitch CSV files together.
Open the SheetXAI sidebar and type:
Fetch the full Omnisend contact list into my Excel cleanup workbook with ID, email, name, and status, then add a column marking rows where the email appears on multiple rows so I can remove duplicates.
SheetXAI pages through the Omnisend contacts endpoint until it has every record, writes them into the workbook, and adds a column marking any email that appears more than once.
What You Get
Your full Omnisend contact list in the workbook, with duplicates flagged:
- Contact ID — for reference when re-importing
- Email, first name, last name — the standard fields
- Subscription status — so you can see if duplicates have conflicting states
- Creation date — so you can keep the oldest or newest record
- Duplicate flag column — marking every row where the email appears more than once
You decide which duplicate to keep. Ask SheetXAI to keep the subscribed record, or the most recent one, and mark the others for removal.
What If the Data Is Not Quite Ready
Contact cleanup is never straightforward. SheetXAI handles the nuance.
When duplicates have different subscription states
One copy of an email is subscribed, the other is unsubscribed. Keeping the wrong one breaks the campaign.
Find all duplicate emails in the workbook. For each set of duplicates, keep the row with status "subscribed" if one exists, otherwise keep the row with the most recent creation date. Mark all other duplicates as "DELETE" in the flag column.
When you also want to catch invalid email formats
Some contacts got in with malformed email addresses.
In addition to flagging duplicates, add a second flag column. For any row where the email does not contain @ or lacks a domain with a dot, write "INVALID EMAIL." I will handle those separately.
When you want to re-import the clean list to Omnisend
After deduplication, you want the cleaned records pushed back to Omnisend.
After flagging, filter to rows where the flag column is empty (not marked DELETE or INVALID). Run a batch Omnisend contact import for those clean rows, updating by contact ID. Write the batch job ID into cell H1.
When you want the full cleanup pipeline in one shot
You want the pull, flagging, decision logic, and re-import all in one instruction.
Pull the full Omnisend contact list into this workbook. Flag duplicates, keeping the "subscribed" record for each duplicate set (or most recently created if none is subscribed). Mark others DELETE. Flag invalid email formats as INVALID. Then re-import all clean rows into Omnisend via batch API, updating by contact ID. Write the imported count into I1 and the excluded count into I2.
The pattern: pull, audit, decide, re-import — one session, one prompt.
Try It
Get the 7-day free trial of SheetXAI and open an Excel workbook, then ask it to pull and deduplicate your Omnisend contact list. The Omnisend integration is included in every SheetXAI plan. For related workflows, see how to bulk import contacts into Omnisend from Excel or the Omnisend in Excel overview.