Standard Shopping campaigns let you set bids and see search terms per product, keyword by keyword. Performance Max for Shopping automates bidding and placement across Search, Display, YouTube and Gmail from the same feed. Most ecommerce accounts now run PMax alongside a small, protected Search layer rather than picking one.
Start a conversationIf you’re selling online with a product feed live in Merchant Center, the decision in front of you isn’t “should I do Shopping ads” — you’re already there. The real choice is which campaign type surfaces your feed: a standard Shopping campaign (sometimes still called manual Shopping), or Performance Max, which absorbs Shopping into a single automated campaign alongside Search, Display, YouTube, Gmail and Discover.
Google has been steering every ecommerce account towards PMax for a couple of years now — it’s the default recommendation in-platform, and Smart Shopping was retired in its favour. That doesn’t make it the wrong choice. It does mean the decision deserves more thought than just accepting the recommended setup, because the two campaign types hand you very different levels of control over the same product feed.
Both campaign types pull products from the same Merchant Center source, use the same product data, and compete in the same Shopping auctions. The difference isn’t what gets shown — it’s who decides what gets shown, at what bid, and how much of that decision you can see afterwards.
Standard Shopping is a single-channel campaign: it shows product listings in Shopping results and the Shopping tab, and nowhere else. You choose the bidding strategy (manual CPC, or a Smart Bidding strategy like target ROAS or maximise conversion value — Google retired enhanced CPC for Shopping campaigns back in 2023), you can set that bid at product group level, and every click ties back to a query you can see in the search term report.
Performance Max is a multi-channel campaign built around your conversion goal rather than a single channel. It still uses your Shopping feed as one of its asset sources, but it decides on every impression whether the best opportunity is a Shopping listing, a Search text ad, a Display placement, a YouTube view, or a Gmail promotion — and moves budget between those channels automatically, in real time, based on what the algorithm predicts will hit your target ROAS or CPA.
PMax takes the same product feed and lets Google’s algorithm decide, in real time, whether a given product should be shown as a Shopping listing, a Search text ad, a Display banner, a YouTube pre-roll or a Gmail promotion — all funded from one budget, all optimising to one conversion goal. You feed it the product feed plus any additional assets (headlines, images, video) and audience signals, and it finds combinations that convert.
What you lose is granular visibility. PMax now has a search terms report alongside its Insights tab, but it’s still less complete than Shopping’s — lower-volume queries get bundled into an “Other search terms” catch-all rather than broken out individually. You can’t set different bids per product group; bidding is handled entirely by the algorithm against your target ROAS or target CPA. And while you can now add negative keywords directly at campaign level in PMax, there’s still no ad-group-equivalent granularity, and negatives only apply to Search and Shopping inventory, not Display or YouTube. For a feed-heavy ecommerce account, that’s still a meaningful amount of the control you’re used to having over Shopping specifically.
There’s also a structural difference in how spend gets allocated across your catalogue. In standard Shopping, you decide how much budget your best-margin products get relative to your loss leaders, because you’re setting bids at that level yourself. In PMax, the algorithm allocates spend towards whatever it predicts will hit your target ROAS or CPA — which is often your best-selling products rather than your best-margin ones, unless you’re feeding it margin data explicitly through custom labels and building your goals around that.
In a standard Shopping campaign, you can open the search term report and see “which exact query spent £40 on Product X this week” for every query, however small. PMax now has a search terms report too, but lower-volume queries still get bundled into an “Other search terms” catch-all rather than broken out individually. If your merchandising or finance team wants a complete, product-level query breakdown to feed back into buying or feed decisions, standard Shopping still gives you that more reliably than PMax does.
The pattern I see work well for ecommerce accounts isn’t PMax-only or Shopping-only — it’s PMax handling the bulk of reach and incremental volume, with a small, tightly controlled Search or Shopping layer protecting the terms that matter most: branded searches, your highest-margin product lines, or exact-match terms you know convert reliably. A protected Search campaign with exact-match keywords still takes automatic priority over PMax for the same query. A protected Shopping campaign doesn’t get that same free pass any more — since Google’s October 2024 update, standard Shopping and PMax now compete on Ad Rank for the same product, so you need a genuinely competitive bid to keep that layer winning, not just a priority setting.
This only works cleanly if your account and conversion tracking are set up to avoid the two campaign types simply bidding against each other for the same customer. Google’s own guidance on exclusions and priority settings is limited, which is exactly the kind of structural decision worth getting an expert set of eyes on before you build it.
The usual objection to running both is cannibalisation — the fear that PMax will simply take credit for sales the protected campaign would have won anyway, inflating apparent PMax performance without adding anything incremental. That’s a legitimate risk if priority and exclusions aren’t configured correctly, but it’s not a reason to avoid the combination altogether. It’s a reason to check the Insights tab and auction data periodically rather than assuming PMax volume is automatically incremental just because the reported ROAS looks healthy.
Yes, and for many ecommerce accounts this is the better setup. Since Google’s October 2024 update, standard Shopping no longer gets automatic priority over PMax for the same product — the two now compete on Ad Rank, so a protected Shopping campaign needs a genuinely competitive bid to win that auction, not just a priority setting. You can still protect specific terms or products this way, but it takes a strong bid rather than priority alone.
Google will often recommend pausing standard Shopping in favour of PMax, but it won’t do it for you. That recommendation suits Google’s goal of maximising spend across more surfaces — it doesn’t automatically suit your goal of keeping control over your best-performing products.
Yes, both campaign types pull from the same product feed in Merchant Center. Feed quality — titles, images, attributes, availability — matters to both, but PMax has fewer manual levers to compensate for a weak feed since bidding and placement are fully automated.
To an extent, yes — Google added a search terms report to PMax, alongside the Insights tab, so you can see many of the actual queries behind your spend. It’s just not as exhaustive as standard Shopping or Search: lower-volume queries get bundled into an “Other search terms” catch-all rather than listed individually, which is still a trade-off for the automation and cross-channel reach PMax offers.
Catalogue size matters less than feed quality and conversion volume. A small, clean catalogue with steady conversion history can do well in PMax; a large catalogue with patchy data or thin product titles often performs better split into well-structured standard Shopping campaigns where you can manage segments individually.
Set campaign priority correctly so a dedicated branded Search or Shopping campaign takes precedence over PMax for those specific terms, and check the PMax Insights tab regularly for signs it’s spending on brand queries you’re already capturing elsewhere. This is a common issue and worth checking properly rather than assuming PMax is finding genuinely new customers.
I manage Google Shopping and Performance Max for ecommerce accounts and can give you an honest read on whether your current setup — PMax-only, Shopping-only, or a mix — is actually the right structure for your feed and margins. Start a conversation.
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