> ## Documentation Index
> Fetch the complete documentation index at: https://docs.msgcompanion.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Sync contacts from your shop

> Bring your shop's customers into Contacts, and what a sync changes and never changes.

When you connect your shop, its customers join your contacts and are kept up to date. You do not need to import a spreadsheet.

<Note>
  Owners and admins connect a shop and start a sync. Managers can see when the last sync ran.
</Note>

## Set it up

Connect your shop under **Integrations**. See [Integrations](/integrations/overview). If no shop is connected, the **Contacts** page shows a **Connect a shop** link.

Only a shop connected on the Integrations page is synced. Installing the Companion app from the Shopify App Store does not sync customers on its own.

## When a sync runs

* When you connect the shop.
* Every night.
* Whenever you choose **Sync from** followed by your shop's name on the **Contacts** page.

While a sync runs, the card at the top of **Contacts** says so, and the page updates when it finishes. Afterwards it shows when the last sync ran and how many contacts were added and updated.

Only one sync runs at a time. If you start one while another is under way, it waits its turn.

## What it brings in

For each customer in your shop:

* name
* phone number
* email address
* notes
* tags
* whether the shop has them as unsubscribed

A customer needs a phone number or an email address. Anyone with neither is skipped.

Each customer becomes one contact. If the person is already in your contacts, the sync matches them by phone number, or by email when they have no number, and updates that contact. It does not create a second one. Their source shows your shop as well as anywhere else they came from.

## What it never overwrites

* **Details you typed.** A name, email or note already on a contact stays. The shop only fills in blanks.
* **Tags.** Tags from the shop are added. None are removed.
* **Opt-outs.** Nothing in the shop's record clears an opt-out held in Companion.

## Unsubscribes and consent

A customer your shop has as unsubscribed is opted out of marketing in Companion.

It only works that way round. "Subscribed" in your shop is consent to your shop's emails, not to WhatsApp. A sync never opts anyone in, and never opts back in someone who has opted out.

Someone you erased while they were opted out comes back opted out if your shop still holds them.

## If a sync stops

The card on the **Contacts** page shows the reason. A sync that stops after repeated errors runs again that night, or you can start it again yourself.

A sync reads up to 90,000 customers. If your shop has more, email [support@msgcompanion.com](mailto:support@msgcompanion.com) and we will bring in the rest.

## Related

* [Contacts](/contacts/overview)
* [Opt-outs](/contacts/opt-outs)
* [Integrations](/integrations/overview)
* [Shopify](/integrations/shopify)


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