In order to ensure your spreadsheet is geocoded properly, you need to check three things before uploading: whether it has headers, formatting the addresses consistently in either single column or multiple-column format, and including country (if geocoding Canadian addresses).
When you upload a file, we only add columns -- we won't delete any information from your spreadsheet. You can see an example geocoded file here.
Acceptable format: multiple-column
Address data (street, city, state, ZIP) are split into multiple columns, and all addresses are formatted in the same way.
Acceptable format: single-column
All of the address data is in a single cell, and all addresses are formatted the same way.
NOT acceptable: Mixed format
Some addresses are formatted in a single cell, and some are spread across multiple cells. This would not process correctly. If your spreadsheet looks like this, you should split it into two spreadsheets. You can do this by filtering for addresses that have a blank second column and copy/pasting them into another spreadsheet.