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Enter your username and password and click "Sign in". You will be redirected to your Google Contacts page. This button is listed in the left panel and will open an import popup window. If you are using the new Contacts preview, this button will be labeled "Contacts". The preview does not currently support importing contacts and you will be redirected to the old contacts interface and will need to redo this step. Browse for the file you exported or created and click "Open". The file will be added to the import popup window. After a few moments the import will complete and your contacts will appear listed on your Contacts page. If you find that your contacts did not import correctly (i.e. information imported into the wrong field), you may have removed a field or missed a comma on your CSV file. If you imported many contacts, it may be easier correct the CSV file, delete all imported contacts, and re-import, rather than editing each contact one by one.
Navigate to Google Contacts in your web browser. Sign into your Google/Gmail account. Click the "Import Contacts" button. Click "Choose File". Select your .CSV file to upload. Click "Import".