How to export and merge contacts from CSV (Google & Outlook)

By Michael, founder of ContactAttic · September 2026 · 7 min read

When you export your contacts, Google and Outlook usually offer you two formats: vCard and CSV. CSV is often the easier one to reach for — but a .csv is really just a spreadsheet of your contacts, so pull a few of them and you're left with duplicate people and columns that don't line up. Here's how to export the CSV from each service, why merging those files by hand is such a slog, and how to fold everything into one clean address book you own.

CSV is the other export format

Alongside vCard (.vcf), both Google and Outlook will hand you a CSV — a comma-separated file where the first row is a list of column names and every row after it is one contact. Open it in a spreadsheet and it looks tidy: one person per line, a column for the name, a column for the email, and so on. That readability is exactly why CSV is often the easiest export to grab. The catch shows up the moment you have more than one of them: a CSV is a snapshot of a spreadsheet, and two spreadsheets don't know anything about each other.

How to export a CSV from Google Contacts

On the web, this takes about a minute:

1. Go to contacts.google.com and sign in.
2. In the left sidebar, choose Export (you may need to select the contacts or a label first).
3. Pick Google CSV as the format. Google also offers an Outlook CSV option here and a vCard option — Google CSV is the fullest layout for Google's own fields.
4. Click Export and save the .csv file somewhere you'll find it.

How to export a CSV from Outlook

In desktop Outlook:

1. Open File → Open & Export → Import/Export.
2. Choose Export to a file, then Comma Separated Values.
3. Select your Contacts folder as what to export.
4. Choose where to save it and finish — you'll get a .csv file.

On Outlook.com, open Settings (or the People view), find the option to export contacts, and download the CSV from there.

The two layouts don't match

Here's the quiet problem: Google and Outlook don't use the same column names. A Google CSV has headers like Name, E-mail 1 - Value and Phone 1 - Value, with numbered columns for each extra email or phone. An Outlook CSV splits the name into First Name and Last Name, and uses headers like E-mail Address, Mobile Phone and Company. Same information, different words for it — so the two files won't stack neatly on top of each other, and neither will a third export from a phone or an old backup.

Why merging CSVs by hand is painful

The obvious move is to open the files in a spreadsheet and paste them together. It disappoints for a few reasons:

• The columns don't reconcile. Google's E-mail 1 - Value and Outlook's E-mail Address mean the same thing, but a spreadsheet treats them as two unrelated columns. You end up hand-mapping headers before anything lines up.
• The same person stays split. If someone is in both your Google and Outlook exports, they're now two rows — and pasting the files together keeps them as two rows. The duplication doesn't get resolved; it gets copied in.
• Sorting isn't merging. Sorting by name lines the duplicates up next to each other so you can see them, but it doesn't combine them. You're still left deleting rows by hand and copying stray phone numbers from one into the other, one person at a time.

The clean way: one address book from every CSV

This is what ContactAttic does in a single pass. It reads contact CSVs directly and — because the two layouts are the sticking point — it recognises both the Google and the Outlook column layouts automatically from the header row. You drop in whichever your apps exported (and vCard .vcf files too, all mixed together), and it:

1. Reads each file in its own layout. A Google CSV, an Outlook CSV and a vCard export are all understood correctly, so you never hand-map columns.
2. Captures every email and phone on each person. The numbered Google columns and Outlook's separate home/work/mobile fields are all kept — nothing gets dropped because it was in "the second email column."
3. Merges everyone who shares an email or phone into one complete card, so the person who was in both exports becomes a single entry that has everything both copies held.
4. Writes one clean contacts.vcf — a standard vCard you can import into Google, Outlook or your phone — plus a structured .jsonl copy and a report of what merged.

It all runs on your own computer: your source CSVs are opened read-only and never changed, nothing is uploaded, and the result is ordinary files you own. Import the single contacts.vcf back into whichever service you like and you're left with one address book, each person once, instead of a folder of half-overlapping spreadsheets.