# Connect eBay, Poshmark, Mercari and other marketplaces

> How to connect each marketplace to Treecat from Settings → Marketplaces, what you need first, and what to do when a login gets stuck.

Source: https://wiki.treecat.io/connect-your-marketplaces · Section: Connecting marketplaces · Updated: 2026-10-21

Go to **Settings → Marketplaces**, click **Add marketplace** and choose the marketplace under **Connect new**. eBay, Amazon, Shopify, Walmart and WooCommerce connect through their official sign-in pages. Poshmark, Mercari, Whatnot, Facebook Marketplace and Etsy connect by logging in once inside the Treecat desktop app. A payment method must be added first.

## Before you start
- **Add a payment method** (with ZIP code) in **Settings → Billing**. Treecat needs one before it can talk to your marketplaces. You are still only charged when a billable item sells. See [Billing, payment methods and promo codes](https://wiki.treecat.io/billing-payment-and-promo-codes).
- **For Poshmark, Mercari, Whatnot, Facebook Marketplace and Etsy**, install the Treecat agent and make sure it is online. See [Install the Treecat agent](https://wiki.treecat.io/install-the-treecat-agent).
- **Be an active seller** on the marketplace. If you have never listed there, create one listing directly on the marketplace first, so its seller settings (payments, shipping, verification) are in place.

## Connect a marketplace

1. Go to **Settings → Marketplaces** and click **Add marketplace**.
2. Choose the marketplace under **Connect new**. (Marketplaces you already use appear under **Add another account**.)
3. Follow the sign-in for that marketplace (see the table below).
4. When the account shows as connected, go to the Inventory page and run an [import](https://wiki.treecat.io/import-listings-and-sales).


## How each marketplace connects
| Marketplace | How you connect |
|---|---|
| eBay | Sign in to the right eBay account in another browser tab. In the **Before you connect eBay** dialog, click **I'm signed in — continue** and approve on eBay. Treecat connects whichever eBay account you are signed in to. |
| Amazon | Approve Treecat on Amazon's consent page. |
| Shopify | Enter your store address (my-store.myshopify.com) and approve the app. |
| Walmart | Approve Treecat on Walmart's sign-in page. |
| WooCommerce | Enter your store address, sign in to WordPress and approve Treecat. |
| Poshmark, Mercari, Whatnot, Facebook Marketplace, Etsy | The login window opens in the Treecat desktop app. Log in there once, on the computer that runs the agent. |

WooCommerce stores then appear in their own WooCommerce section on Settings → Marketplaces, with **Reconnect** and **Disconnect** for each store.

After the first login you can use Treecat from any computer or phone. You only log in again when the marketplace session expires; see [Reconnect a marketplace](https://wiki.treecat.io/reconnect-a-marketplace).

## If the login gets stuck
1. If nothing appears, click **Open app again** in the Connect dialog.
2. If the app is not responding, quit it completely from the menu-bar or tray icon, reopen it, and try again. If that does not help, reinstall the app.
3. If the marketplace shows a block or captcha, wait a few minutes and try again. Repeated attempts can extend the block.
4. Check **Settings → Events** to see where the login stopped.

Common messages in the Connect dialog:

- **"The platform blocked this login attempt."** Wait a few minutes before trying again.
- **"Your Treecat app doesn't support connecting this platform yet."** Update the agent and try again.
- **"The browser engine on your computer updated in the background."** Quit and reopen the Treecat agent, then try again.
- **"You logged in, but saving the account to Treecat failed."** Try again; if it keeps happening, contact Treecat support.

If a connection keeps failing, confirm that you can create a listing manually on that marketplace.

## More than one account per marketplace
You can connect several accounts on the same marketplace. Use **Add marketplace → Add another account**. Each account appears as its own row where you can set the default account, change its settings, pause syncing, or delete it. See [Manage marketplace accounts](https://wiki.treecat.io/manage-marketplace-accounts), and [Move listings between accounts](https://wiki.treecat.io/move-listings-between-accounts).

## Frequently asked questions

### Does Treecat store my marketplace passwords?

No. You log in on the marketplace itself, and Treecat keeps only the resulting login session for that marketplace.

### Why does Treecat ask me to reconnect?

Marketplace logins expire every few months. Treecat shows a Reconnect banner and emails you. Reconnect from **Settings → Marketplaces**. See [Reconnect a marketplace](https://wiki.treecat.io/reconnect-a-marketplace).

### Which marketplaces does Treecat support?

eBay, Poshmark, Mercari, Whatnot, Amazon, Etsy, Shopify, Facebook Marketplace, Walmart and WooCommerce, for US-based stores.

### Why can't I add eBay Canada, the UK or another country?

Treecat supports US marketplaces only. You can manage a US account from anywhere in the world.