Customers
Open in TWICE Admin
Prerequisites
- A CSV with a header row. The importer matches your column names against the ones it expects, and recognises common variants (
first name,firstname,first_name). - A first name and a unique email on every row. These are the two required columns, and a row missing either cannot be imported.
- A deduplicated file. Two rows sharing an email fail each other — see the pitfalls.
The Walkthrough
Prepare the columns the importer accepts
Run Import customers
Read the validation before you commit
Understand that import only ever creates
- You cannot use import to bulk-update customers. Re-importing a corrected file does not fix the records already in TWICE; it fails on every row that matched.
- You cannot import in passes — one file with names, another adding phone numbers. The second pass fails entirely.
- Get the file right before the first run. It is the only run that lands.
Fill in what the import could not carry
- Business customers need Customer type, Company name and Tax / VAT ID set — see Set up business customers.
- Addresses are empty and have to be added where you invoice or deliver.
- Tags and attributes are unset, so any segmentation you had is gone. Rebuild it — see Segment customers.
How do I know it worked?
- The customers table row count matches your file, less any rows you knowingly dropped.
- A sample of records reads correctly — spot-check a few, especially any with accented characters or unusual phone formats.
- Marketing consent is true only where it should be, which is worth filtering the table to check before you send anything.
- Language is right, since it decides which language each customer’s emails render in.
Troubleshooting / Common Pitfalls
"Email already exists for another customer"
"Email already exists for another customer"
"Email must be unique" on rows that look fine
"Email must be unique" on rows that look fine
I re-imported a corrected file and nothing changed
I re-imported a corrected file and nothing changed
My customers have no company details after importing
My customers have no company details after importing
A row has no email and I want to import it anyway
A row has no email and I want to import it anyway
The file is very large
The file is very large