Google would love your entire budget in Performance Max: one campaign, every surface, trust the machine. Sometimes the machine deserves it — PMax can find converting inventory a human never would. But it will also happily spend your money answering searches for your own brand name and call it incremental growth. Here’s how we split budgets between PMax and Search, and the guardrails that keep the black box honest.
What each campaign type is actually good at
Search: intent you can read
A Search campaign is a glass box. You choose the queries, you read the search terms, you write the ads, you set the negatives. For high-intent commercial queries — “shopify development agency”, “buy running shoes online” — nothing beats owning the exact moment of demand with a message you control. Search is also where your brand terms live, and those deserve their own campaign with its own (modest) budget, because mixing brand with non-brand is how accounts flatter themselves.
Performance Max: reach you can’t buy manually
PMax spans Search, Shopping, YouTube, Display, Gmail and Discover from one campaign, using your feed and assets to chase conversions wherever they’re cheapest. For e-commerce with a product feed it’s close to mandatory — it has effectively absorbed Smart Shopping — and it genuinely finds pockets of converting inventory nobody would target by hand. The price is opacity: limited search-term visibility, blended placement reporting, and a strong appetite for taking credit.
The honest split
- Brand Search — always separate. Cheap insurance, clean data, and the first place to run an incrementality holdout.
- Non-brand Search — your highest-intent commercial queries, exact and phrase, with aggressive search-term hygiene. This is the backbone for lead-gen accounts.
- PMax — the e-commerce workhorse for feed-based selling and the scale layer once Search has proven the economics. Feed it your best assets and real conversion values, and give it room: it needs conversion volume to learn.
- Brand exclusions on PMax — non-negotiable. Without them, PMax cannibalizes your brand traffic and reports it as performance.
Keep PMax honest with three checks: brand exclusions applied at the campaign level; new-customer weighting (or new-customer-only goals) so it optimizes for growth rather than harvesting; and a quarterly look at what happens to Search volume when PMax budgets move — if Search impressions fall as PMax rises, it’s eating your glass box, not expanding your reach.
Value-based bidding changes the answer
Both campaign types are only as smart as the conversion signal you feed them. Accounts sending real margin data — or at least differentiated conversion values — consistently outperform accounts optimizing to a flat “purchase”. If every conversion is worth 1, the algorithm will cheerfully buy you low-value customers at scale. Fix the signal before you argue about campaign types: with value-based bidding in place, tROAS targets on both PMax and Search start meaning what you think they mean.
Where the traffic lands still decides the ROAS
PMax and Search can only bid their way to the click. What the click is worth is decided by your product page and checkout — which is why we treat performance marketing and conversion optimization as part of the same engagement, not separate services. A tROAS target your landing page can’t support just teaches the algorithm to spend less.
Frequently asked questions
Should I run Performance Max and Search campaigns at the same time?
Yes — they’re complementary. Search owns readable high-intent queries and brand terms; PMax scales across Google’s full inventory. Apply brand exclusions to PMax and watch for cannibalization.
Why is my Performance Max ROAS so high?
Often because it’s answering branded searches and retargeting warm audiences — conversions that would largely have happened anyway. Add brand exclusions, weight new customers, and check blended revenue against budget changes.
How much conversion volume does Performance Max need?
Roughly 30 conversions per month per campaign minimum — ideally 60+. Below that, consolidate campaigns or lean on structured Search until volume supports automation.
Is Performance Max worth it for lead generation businesses?
It can work, but lead-gen PMax is prone to junk leads because every form fill looks equally valuable. It needs offline conversion imports or lead scoring feeding real values back — without that, structured Search usually wins.
The takeaway
Search where you can read intent, PMax where the feed and the machine can hunt, brand always fenced off and always excluded from the black box. Feed both real conversion values, judge both on blended results rather than their own reporting, and remember the landing page sets the ceiling that no bid strategy can raise.