Merchant Center in Performance Max: how to link your feed and advertise products

Quick answer

To use Merchant Center in Performance Max, first link Merchant Center to Google Ads: the request starts in Merchant Center and a Google Ads admin approves it. Then pick the Merchant Center account on the campaign. With no feed label, PMax uses all products; with a label, only that feed's products. Check the listing groups.

What changes in Performance Max with Merchant Center attached?

PMax stops advertising just the message and starts advertising products: the photo, price and name of each item in the feed, on Shopping and across Google's other channels. What the Google Ads API documentation says about retail PMax, checked October 17, 2026:

• To use Performance Max for retail, the Google Ads account must be linked to an existing Merchant Center account.
• The Merchant Center ID is required: it is the account that holds the products to advertise.
• The feed label selects products from a specific feed. Without it, the campaign uses all available Merchant Center feeds.
• Every asset group needs a valid listing group tree. A single-node tree that includes all products meets the requirement, and ads won't serve without a valid tree.

The rest of the asset group still applies: headlines, images, logo and videos. The minimums are in Performance Max asset groups.

How do you link Merchant Center to Google Ads?

The link is the step that stalls most often, because it involves two accounts and usually two people: the store owner, who runs Merchant Center, and the agency, which runs Google Ads. Per Google Merchant Center Help, checked October 17, 2026:

1. In Merchant Center, someone with admin access opens Settings, then Access and services, then Apps and services.
2. They click Add service, choose Google Ads, select the account and finish with Link. Only a Merchant Center admin can start the request.
3. In Google Ads, an account admin opens Tools, then Data manager, finds Google Merchant Center under connected products and selects Manage & link.
4. On the Received tab, the request shows as needing approval. Review and approve it to finish. Only a Google Ads admin can approve.

What is a feed label, and when should you use one?

A feed label is the tag that separates feeds inside one Merchant Center account, for example a US feed and a CA feed for a store that sells in both countries. In PMax it decides which products go in:

A label that does not exist in Merchant Center leaves the campaign with no products. Copy the label from Merchant Center instead of typing it from memory.

How do you attach Merchant Center to PMax in Ads Editor?

Since October 13, 2026, Ads Editor's Google manager attaches Merchant Center to PMax, both when creating a campaign and on a PMax that already exists.

1. New PMax: in Ads Editor's Google Ads manager, click the green Create campaign button and choose Performance Max.
2. On the search themes step, a Merchant Center / Google Shopping block appears. Pick the Merchant Center account linked to the Google Ads account; if there is only one, it is preselected. No product catalog creates PMax without products, as before.
3. Feed label (optional): fill it in only if your feed has a label. Empty uses every product in Merchant Center.
4. Existing PMax: open Edit asset group on the campaign. The same block is there; pick the Merchant Center account, the label if any, and save.
5. The campaign goes live with all products in the feed: every asset group that had no products gets all of them. Narrowing by brand, category or product is done afterwards in Google Ads.

If Merchant Center is not linked to the account, Ads Editor refuses before creating or saving and shows any pending link requests. It does not create the link for you: that still happens in Merchant Center and Google Ads. From an AI chat, the Ads Editor MCP lists the account's Merchant Center accounts and attaches one to an existing PMax.

Google Ads or Ads Editor: who does what with Merchant Center?

Why isn't Performance Max showing my products?

• The link was never approved. The request left Merchant Center and is waiting on the Received tab in Google Ads.
• An asset group has no listing group tree. Without a valid tree, Google's documentation says ads won't serve.
• Wrong feed label. The campaign's label matches no feed in Merchant Center.
• Products disapproved in Merchant Center. The campaign only advertises what Merchant Center approved; check feed issues there.

For the weekly routine across many Google Ads accounts, with bidding, negatives and PMax, see how to manage Google Ads for multiple clients.