How to Import Contacts in Outlook 365

To import contacts into Outlook 365, prepare a contact list as a CSV file, open the People or Contacts area, and choose the import option. You can import through Outlook on the web or the new Outlook for Windows; classic Outlook for Windows has a separate Import/Export wizard. Before starting, check that the file has a header row and that you are signed in to the account where you want the contacts saved.

What You’ll Need

A CSV file containing your contacts. Outlook’s contact import tools generally expect CSV rather than an Excel workbook, so save an Excel list as a comma-separated values file first.
A header row identifying each column, such as First Name, Last Name, E-mail Address, Mobile Phone, or Company. Clear headers make it easier to identify and map the data.
Access to the correct Microsoft 365 or Outlook account. Imported contacts are added to the account you are signed in to, not automatically to every account in Outlook.
A backup copy of the source file. Keep the original spreadsheet or export available in case you need to correct the columns and try again.

If you are starting in Excel for Windows, use File > Save As, choose a location, then select CSV UTF-8 (Comma delimited) (*.csv) as the file type and save. Excel may warn that CSV format does not preserve multiple worksheets or workbook features; that is expected. Only the active worksheet is saved, so put the complete contact list on one sheet before exporting.

Step-by-Step

Check and prepare the contact list. Put one person or organization on each row, with one type of information per column. Use a header row in the first row and avoid merged cells, blank rows in the middle of the list, and titles or notes above the headers. For example, columns might be First Name, Last Name, E-mail Address, Business Phone, Mobile Phone, and Company. Check that email addresses and phone numbers are in the correct columns. If a phone number starts with zero or includes a country code, set that spreadsheet column to Text before entering or importing data, so Excel does not remove meaningful digits. Save as CSV UTF-8 and keep your original workbook as a backup.
Choose the Outlook account and interface you want to use. Sign in to the intended Microsoft 365 account. In Outlook on the web, open the People app using the People icon in the left navigation. In the new Outlook for Windows, open People from the left navigation as well. If your interface is classic Outlook for Windows, use the classic Outlook steps in step 6 instead. If several accounts appear in Outlook, verify the account name or address before importing; a contact list imported to one mailbox will not necessarily appear in another.
Open the contact import command in Outlook on the web or new Outlook. In People, select Manage contacts, then choose Import contacts. In some layouts, the command may be displayed directly in the People toolbar; look for Import contacts if Manage contacts is not shown. Browse to the CSV file you saved and select it. Confirm that the displayed filename is the right one before continuing. Do not choose an Excel .xlsx file if the import dialog asks for a CSV file.
Start the import and wait for confirmation. Select Import in the file picker or import panel, as applicable. Keep the Outlook page open while it processes the file. A completion message or updated contact list indicates that the import has finished. If Outlook reports a file problem, do not repeatedly import the same list without checking the contact list first; a second attempt could create extra copies if the first import partially succeeded.
Check the imported records. Return to People and search for a few names from the source list. Open several contacts to confirm that names, email addresses, phone numbers, and company details appear in the intended fields. Also check a record with an unusual value, such as a long international phone number or a name with an accent. This small review can reveal a column issue before you rely on the full list.
For classic Outlook for Windows, use the Import/Export wizard instead. Select File > Open & Export > Import/Export. Choose Import from another program or file, select Comma Separated Values, and browse to your CSV. Choose how to handle duplicates if the wizard offers that choice: replace duplicates with imported items, allow duplicates, or do not import duplicates. Select the Contacts folder for the mailbox where the contacts belong, then continue. If the folder list includes multiple mailboxes, carefully select the right account’s Contacts folder.
Map columns in classic Outlook if needed, then finish. When the wizard reaches the field-mapping screen, compare the CSV column names on the left with Outlook contact fields on the right. Drag a source field, such as E-mail Address, onto the matching Outlook field if Outlook has not matched it automatically. Map only fields that contain data you want to import. Select OK, then Finish. Open the Contacts or People view and inspect several records. If you use Outlook on a Mac, its desktop menus differ from the Windows wizard; importing through Outlook on the web is a practical alternative because it uses the People import workflow described above.

Common Mistakes

Trying to import an Excel workbook directly: The standard contact import workflow uses a CSV file. Save a copy as CSV UTF-8 rather than renaming an .xlsx file to end in .csv; changing the extension does not convert the file.

Saving the wrong worksheet: Excel’s CSV export saves only the active sheet. If the contacts are on a different tab, activate that tab before saving. Reopen the CSV, if possible, to confirm it contains the expected rows and columns.

Using unclear or missing headers: A file without a header row can make fields difficult to identify, especially in classic Outlook’s mapping wizard. Keep a descriptive header row and avoid putting a report title or explanatory note above it.

Importing to the wrong account or folder: Outlook can show more than one mailbox. A successful import may appear to have failed if you are looking at the Contacts folder for a different account.

Importing repeatedly without checking: Some routes may allow duplicate records, while others handle them differently. Check People after a failed or interrupted attempt before running the import again.

Tips

Test with a small CSV containing two or three contacts before importing a large address book. Confirm that the fields land correctly, then use the full file.
For the most dependable headers, export a small set of existing contacts from the same Outlook account and use its column names as a guide. Remove sample personal data before sharing the file.
Use one row per contact and keep each data type in its own column. Put an additional email address in an appropriate secondary email column if your source format and Outlook mapping support it; do not combine several addresses in one cell unless you have confirmed how the import handles them.
Keep a copy of the CSV and the original spreadsheet until you have checked the imported results. If you need to correct a mapping or spelling issue, you can amend the source rather than rebuilding the list.
For a large list, import in manageable batches and note which rows belong to each batch. This makes it easier to identify a problematic record and reduces the effort needed to retry only the affected data.

Troubleshooting

The import option is missing. Make sure you are in People, not the Mail view. In Outlook on the web or new Outlook, look for Manage contacts and then Import contacts, or check the People toolbar for Import contacts. If you are using classic Outlook for Windows, use File > Open & Export > Import/Export instead. If a work or school account has a restricted interface, ask your Microsoft 365 administrator whether contact import is available.

Outlook rejects the file. Confirm that the file is truly saved as .csv and that it opens as a readable table in a spreadsheet editor. If you exported from Excel, save again as CSV UTF-8. Remove empty top rows, merged cells, and extra title lines, and check that the CSV is not open or locked by another program. If necessary, create a small fresh CSV with a header row and one test contact to find out whether the issue is with the file or the import process.

Contacts imported, but details are in the wrong fields. This is often a header or field-mapping problem. In classic Outlook, repeat the wizard and map the CSV fields to the matching Outlook fields before selecting Finish. In the web or new Outlook workflow, correct the source headers and data, then test with a few records. If the wrong contacts have already been added, review them before importing again so you do not multiply the errors.

Some contacts are missing or duplicated. Check the CSV for blank rows, repeated entries, and data placed outside the populated table. Search for a missing contact by email address as well as by name; names may be formatted differently. Classic Outlook’s wizard includes duplicate-handling choices, but do not assume every Outlook version uses the same rule. If you see duplicates, remove or merge them carefully and choose a consistent duplicate policy for any later import.

Accents or symbols look wrong. Save the source as CSV UTF-8 and retry with a small sample containing the affected characters. Also verify that the CSV opens correctly before importing. If the sample is readable in the file but still appears incorrectly in Outlook, use the web import route or ask your Microsoft 365 administrator to check for account-specific restrictions.

Frequently Asked Questions

Can I import contacts from an Excel file?
Save the contact worksheet as a CSV file first. Outlook’s contact import workflow expects CSV in the routes covered here; saving a copy preserves your original Excel workbook.

Will importing contacts replace the ones already in Outlook?
It depends on the import route and duplicate handling. Classic Outlook’s wizard lets you choose how to treat duplicates. Other interfaces may handle them differently, so check your contacts before retrying and do not assume an import will merge every matching record.

Where do imported contacts appear?
They appear in the People or Contacts area of the account and folder you selected or were signed in to. If they are not visible, check the active account and search for one imported email address.

Can I import contacts into Outlook on my phone?
The steps in this guide use Outlook on the web or desktop Outlook. Mobile app features can differ, so import the CSV through Outlook on the web or a computer, then open the same account in the mobile app.

Can I import contacts from Gmail or another email service?
Yes, if you can export the contacts from that service as a CSV file that Outlook can read. Review the exported column headings and test a few records first, since field names and available contact details vary between services.

Why are some phone numbers missing a leading zero?
Spreadsheet software may interpret phone numbers as numbers and remove leading zeros. Set phone-number columns to Text before entering or exporting the data, then verify the CSV and imported records. Phone numbers should be treated as contact details, not values for arithmetic.

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Sources: Function behaviour and menu paths: Microsoft Support documentation for Excel. Method & sources

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