Short answer
To send bulk SMS from Excel or CSV, put one phone number per row in international E.164 format, add a country column and merge fields such as first name, remove duplicates, invalid numbers and opted-out contacts, save as CSV, upload it to your messaging platform, preview the merged text, send a test to your own number, then send or schedule by time zone and export the delivery report.
Prepare the sheet
Use one row per recipient. Keep merge fields in their own columns without spaces in the names, with one header row and no blank rows or totals.
Format the phone column as Text before pasting numbers. Excel otherwise drops leading zeros and shows long numbers in scientific notation.
| phone | country | first_name | language |
|---|---|---|---|
| +971501234567 | AE | Layla | en |
| +966512345678 | SA | Omar | ar |
| +254712345678 | KE | Amina | en |
Clean, test and send
- Normalise every number to E.164, then remove duplicates and invalid numbers.
- Remove landlines and opted-out contacts; consider an HLR lookup for inactive numbers.
- Upload, map the phone and merge columns, and preview the merged message with your longest values.
- Send a test to your own number and check names, sender ID and segments.
- Split the list by country and schedule each batch inside its own sending hours.
- Export the delivery report as CSV and remove numbers that failed.
Watch message length
An SMS carries 140 bytes: 160 characters in GSM 7-bit or 70 in Unicode, which Arabic and emoji need. Longer messages split into segments of 153 or 67 characters, and each segment is billed (3GPP TS 23.038 and 23.040). A long merged name or one Arabic character can change the segment count, so preview the longest row.
Official sources
- Recommendation ITU-T E.164: The international public telecommunication numbering plan
- Keeping leading zeros and large numbers — Microsoft Support
- Import or export text (.txt or .csv) files — Microsoft Support
- 3GPP TS 23.038: Alphabets and language-specific information
- 3GPP TS 23.040: Technical realization of the Short Message Service (SMS)